Actually, platys and other livebearers (swordtails, black mollies, guppies etc) don't need much to have fry regularly. I had a huge bunch of guppies in a bowl when I was small and they had babies all the time, I even gave some away and my other friends had some large jars (I'm talking 5+ liters) that they kept their guppies in).
Livebearers will generally have babies every month and they're very hardy fish good for beginners to keep. Can be pretty gratifying as well to see them "thrive" in your care

("thrive referring to the bowls and jars mentioned earlier)