A basic body exercise, the push up is an easy way to start and maintain fitness.
The way to build up is to first do as many as you can with good form. Let’s say you do 20 . OK, now rest and count to 20 seconds and hit it again. This time , perhaps you only do 12 . No worries. Count to 12 and do it again. Do this till you can’t even do one.
A great long term goal, especially for seniors is to always be able to do ONE push-up for every YEAR you’ve been alive.