Any advice you’ve ever heard or given. I linked a great video that I think would be my answer, combined with the “stop caring what other people think about you” and “comparison is the thief of joy” comments below. Just do stuff that you wanna do, don’t compare and don’t care what others say. It’s awesome advice.
Take care of your body. Teeth, bones, joints, muscles, and skin can all be repaired but it’s never as good as a factory original.
Also, those repairs cost time and money. My father in law is almost 20 years younger than my dad and can’t do as much in a day as my dad. He’s shortened his quality life because he thought shrugging off problems was what you should do.