Gradualism is the key. Both your arm muscles and your heart must be up to the job. Making a very easy selection is not silly. Reach high numbers on a very easy task before increasing the difficulty.
You may be surprised by how difficult it becomes to get up off the floor if you haven't tried to do this in years. Pushups on stairs is a way back. As you age, it becomes a safety issue.
You may feel that your arms are strong enough for what you normally do, but if you can regain your ability to do pushups, your health may improve. As always, check with your doctor about this and other home exercises.