inIn general, cats stop growing when they are one year old,thisold; this means your cat will not get longer or taller, and the growth stop is gradual, not a sudden stop.
In https://petsthis article on pets.thenest.com/kitten-considered-fully-grown-4251.html you could find more information about growth of cats.
aA cat will continue to develop for another year until it looks like an addultadult cat, but the changes are relative small.
iI am a little consernedconcerned about the weight of your cat,acat; a two year old cat is normally not overweight due to the normal playfulness at this age and the energy used when it plays.
a link with some information:Here is the http://cattimearticle about American short-haired cats on cattime.com/cat-breeds/american-shorthair that contains some more information.
youYou need to give the cat a food formulated for spayed/neutered cats and, establish fixed feeding times and do not feed more than the instruction on the package saysays.
youYou have to stop giving treats to your cat, or atleastat least only give treats once a week,and and do not feed your cat foodscraps at all.
iI am not saying you do any of this,so so please see this as a general advice.
andAnd last: play more with your cat and keep him active more of the time,maby maybe give him more/other toys cats. Cats like variation when they play, so they do not get bored.