The feeling of fitness depends entirely on arm strength.
In fact, doing push-ups is the same as doing barbell bench presses in the gym, just standing upside down. One lifts the barbell, the other lifts himself. When I do bench press for the first time, I always feel my shoulders ache and I can't feel the strength of my chest muscles. But after a long time, the standard will be fine. If the push-ups are standard, the chest muscles will definitely exert their strength. If you can't feel it, let a friend touch your chest muscles next time, and you will definitely contract when you push hard.