Seconded on getting sufficient sleep, since COVID happened my wife and I have been sleeping later. We used to get to bed by 12, but dragged to 1 or 2am, 3am when Animal Crossing was out, getting somewhere between 5-7 hours a night.
Recently made a pact to sleep by 12 and avoid coffee after 12pm and we are sleeping much better. Feeling way less tired throughout the day and less sore.
Regarding a regime for 20 year olds - wouldn't hurt to eat right, do your strength and conditioning, stretching and sleeping right, older you will thank you for taking care of yourself. I would add that you should take time off to rest and properly rehab when injured, your youth wont last forever and stacking up injuries is a sure fire way to be groaning in pain every morning.