If i do alot of pushups will i get bigger ? honestly?

if i just do a whole bunch of pushups every day will i get bigger or no? i always wondered because my brother use to be in the military and to this day i have seen him do so many pushups a day like more than an average person he would always ace his PT test in the military but he's had the same body type as when he was 17 no lie. I Asked him about it and he said pushups aren't suppose to make u buffer but just in shape. IDK what thats suppose to mean cuz i mean guys in prison get super big