Playtime=vicious biting and growling (long)

I can tell you right now it's not a pack thing - we now know that dogs aren't actually pack animals (social, yes, but they don't 'pack' the way that media would have us believe), don't have strict hierarchies of rank, and certainly don't see or interact with humans as they would other dogs anyway.

These all just sound like puppy things - he simply hasn't learned how to play appropriately. I'd suggest doing a lot more management. Baby gates and playpens are your friends - right now 'ignoring' isn't working because the puppy still has access to you and can get a reaction. If you set up a gate or pen, you can simply step over the barrier every time teeth touch skin, and can wait comfortably and unharrassed until the pup is calmer and you want to try again. Same with the couch issue. You need to block access to the couch for now, and also make sure your puppy has a comfortable bed of his own that he gets rewarded for using (praise, treats, long-lasting chews or puzzle toys). Keeping him from practicing the unwanted behavior and giving him an alternative to use instead will go a long way towards forming the habits you want him to have as an adult.

If gates and pens aren't doable, you can also tether the pup and step out of range when he gets too rough, but ONLY do this when you can supervise. It's otherwise too easy for puppies to get tangled and wind up choking or otherwise hurting themselves, or for them to chew through the lead (which is another habit you don't want him to learn!).

You are absolutely right about smacking being a bad idea. At best, your pup will think it's a great game and escalate his own roughness to match. At worst, you'll wind up with a dog afraid of you and/or hands in general, which can lead to defensive biting and a whole lot of handling and behavior issues. Hand-shy dogs often struggle with having their collars put on and off, recall, unexpected fast movements in their vicinity, and can be a nerve-wracking nightmare around grabby toddlers. No hitting or rough handling, period. There are better ways.

As an aside, some dogs are just loud players. This isn't inherently bad, and might never go away. My 6 year old still growls, grumbles, and makes all kind of weird noises when playing, but also has really good control of his mouth and teeth and never deliberately nails us (occasionally he'll misjudge a grab at a toy, but it's always clearly accidental). His play noises sound different than when he's actually upset, and you'll probably learn the difference with your pup as he grows and you get more familiar with each other.

Don't smack your puppy for biting. He won't understand. He'll either think that you're playing rough and he'll keep on biting or he'll learn to be afraid of you.

I'm sure someone with lots of puppy training experience will come along with a reply in the next 24 hours. In the meantime, I'll tell you what I did with my last dog.

If Frankie bit me too hard with those needle sharp teeth, I'd let out a high-pitched "ouch" to let him know that he hurt me. Then I'd quit playing with him for at least several minutes. After awhile, I'd go back and we'd do it all over again. We would play, he'd bite too hard, I'd yelp and immediately get up and quit playing. As I recall, it took several weeks for him to get the message. At first, he didn't think much of my yelps. Then, he'd sit back and look at me in surprise, like he was trying to figure out why I was such a wimp. LOL Those moments got to be fewer and fewer and then he just stopped biting. He turned out to be a very gentle dog.

I plan to use the same technique with my soon-to-be new puppy, except that I'll also provide more outlets for her to chew. I plan to feed my new pup a portion of her food in a Kong toy. I bought a nylabone that I hope she'll gnaw on. And I bought a little rope toy so she can use her chompers to play tug. Puppies and dogs need to chew. It's just part of who they are. If you don't give them something appropriate to chew on, they'll find something on their own. My last dog chewed up the legs on my kitchen chairs.

Whoops, I took a break before finishing my post and Daysleepers left a great answer ahead of me.

Thanks for the advice. As I said, I don’t want to hit him, however I also don’t want to let him rip my arm off ? Btw right now he is curled up next to me and he doesn’t have a problem with me petting him.

I will try using that sour Apple spray on my hands to see if he stops the biting...

Today was a day of experiments for us. He is amazing really, barely had any problems with taking a bath, or walking on a leash. He pulled a little but that is fine, easily corrected.

While I'm at it, let me mention some other stuff that I noticed.
He has serious problems with being alone. Like sorry but I can’t go to the toilet without him selling the house with his howls and whines. All of us are working or going to school on weekdays but my mom comes home a couple of times to check on him, feed him etc. He is never alone for more than 2 hours at a time.
We do not have a crate because we never had to use one with our prev dog so yeah. We are also not a fan of leashes and stuff.
I hope he gets used to being left alone for a few hours...

We have a couple of rooms and places that are barricaded agains the puppy but this silly bugger is an escape artist. ?
He loves toddlers but is scared of bigger kids and dogs.

I introduced him to the neighbour dog but the neighbour dog kept attacking both of us. The neighbour dog is a big German Sheperd mix and he can jump over the fence separating our yards. He is not trained at all and is quite agressive. He hated and bit my older dog too.
So going out to play is an issue.

This feels like a huge mess right now ...

Anyway Thanks again for the good advices!

This is very, very normal puppy behavior. You've already received some great advice.

Make sure your pup has plenty of appropriate toys. Keep one near you when you play. If puppy bites you, redirect to a toy and praise him for using it. If he continues to bite you, get up and end play. Step over a baby gate, close a door, whatever, just withdraw attention for 5-10 minutes. After that time, try again. Rinse and repeat. This a slow process. It will not happen overnight! You must be patient and consistent for many months before the pup understands that when his teeth meet your flesh, playtime ends.

Whining and howling when being left alone is normal puppy behavior, too. They have to be taught to accept being alone, and sometimes that means letting them cry. Try leaving the pup with a really yummy treat, like a Kong stuffed with a bit of wet dog food and peanut butter, then frozen.

I would avoid your neighbor dog at all costs, and talk to your neighbor about him getting into your yard! That is not okay! If it keeps happening and your neighbor does nothing, I would be calling authorities because that is not safe.

It's great that your pup isn't showing fallout from the hitting so far! Unfortunately, the nature of that kind of correction is that the dogs tend to get used to it (esp. with a growing puppy) and you have to make it more and more severe to be effective. Really bad road to go down, I'm sure you can imagine. It's best to change your approach now, before you get into a battle of wills and damage your relationship with your dog.

I like a crate, assuming it's introduced correctly to a pup as a positive space, but I'm not going to tell you that you absolutely need one in this situation. But you do need management. I can totally appreciate that it doesn't feel great to limit your puppy's freedom, but it's not forever. Restricting your pup's choices now is going to set them up for learning how to behave in the future, and allow them to have a lot more freedom as an adult. It can also be key to avoiding a pup chewing inappropriate things, eating things they shouldn't, or otherwise getting into trouble when they're in the worst of those puppy stages.

Work on those barricades, and use them when your pup gets mouthy and needs a time-out. I do like an exercise pen setup, which gives a pup more space than a crate does, and are pretty easy for the human to step out of (or into!) when you need to get out of reach of those land-shark teeth. Emily Larlham (Kikopup on YouTube) has a great video on training a puppy to be alone, and has a lot of informative content in general if you're interested: https://www.youtube.com/watch?v=LGxhcb-itO4&t=

Agree that the neighbor dog is a scary situation. If the neighbor is unwilling or unable to contain their dog, it might be worth escalating things to the local animal control or other relevant authorities.