Pushups work your upper body. Specifically your chest, lats, shoulders, and triceps.
It depends on which muscles you focus on and how strong they are. Generally you use the muscles that you are most comfortable with or that are the most developed. For me, triceps are more developed than my chest. So I don’t like doing too many pushups because it makes my arms look huge.
But sometimes when my triceps are sore I do pushups and focus on my chest muscles, thats when it works my chest more.
Lats and shoulders are the same, you need to focus on flexing those muscles to work them out.