>>84106612feeling sore is fine
how many a day doesn't tell the whole story, what matters is going close or to failure in a reasonable rep range (if you're doing over 30 reps in a set find a harder variant, there's bad diminishing returns.) overall volume still matters too but if you're doing say 5 pushups in a set and you stop when you could get out like 10 more, you're not really going to grow much
i would recommend deficit pushups instead of knuckle pushups because they give the same increased ROM while being kinder to your hands and wrists. you can accomplish this by using anything that elevates your hands, such as a pile of books
