Putting on my mod hat for a minute - it's against forum rules to sell or rehome animals here, so if you're looking to arrange an adoption through this site that won't be allowed. However, we can absolutely give advice about finding available pups.
It's unlikely you'll find a baby puppy available for free, especially right now where Covid has increased the demand for pets so much. Your best bet would be watching Craigslist or similar sites for people rehoming dogs at low cost, but rehoming fees are very normal even there. You say puppies - are you looking for more than one? What kind of traits are you looking for? There's a huge variety of temperaments, energy levels, coat types, etc. with small dogs, so size alone isn't going to guarantee they're a good fit for your household. Even if you wind up with a mixed breed, having some idea of what you want in a dog will help you avoid winding up with a puppy that just isn't a good fit. Shelties, for example, are notorious barkers and might not be good fits for apartment life, while dogs with long coats and/or curly coats like poodles, bichon, Shih Tzu, etc. require regular coat maintenance (brushing/combing) as well as trimming (or shaving) as often as every 4-6 weeks, depending on how short you keep their fur.
Understand that upkeep and vetting for dogs can be expensive, especially if you get puppies that will need their vaccines, spay/neuter, microchip, etc. Whether or not you pay for the dog itself, it's important to have savings or the financial means to cover necessary costs, including grooming (whether you want it done professionally or are willing to do it yourself) if the dog requires it, and at least minor emergencies.