OP, puberty begins when your hypothalamus starts to kick up the production of gonadotropins at around age 10-13, and it ends when the last bones fuse in your mid 20s which are the clavicles, scapula, hip, vertebra. However, the bones which actually contribute to height the most, the legs, are usually done growing by 16-18 years of age in men. At this point only, an inch or so can be gained in the torso. That’s the average.
If you’re young enough, you can of course go on growth hormone and /or prolong closing of growth plates with aromatase inhibitors. Aromatase inhibitors you can get from gymbros and j00ce slingers at any commercial gym, would recommend to get pharmaceutical grade.
GH you can get online or from a doctor (unlikely but possible) or from a friend if you know any serious high school or college athletes, but you’d have better luck perhaps getting it online or even better, also buying GH peptides and mk677 online , which are unscheduled, legal, and easy to get