Matthew Walker, PhD is a sleep scientist. I first heard about him on Joe Rogan's podcast. I credit his interviews and his book Why We Sleep with kicking me into high gear to improve my sleep. If you don't have time to read his book, at least carve out 19 minutes and listen to his TED talk Sleep is your superpower.
As @abrahamKim pointed out, sleep is the fundamental pillar that provides the foundation for health.
Last night I achieved a sleep score of 91 (out of 100) as measured by my Oura ring. I slept for a total of 7h 49m. My sleep wasn't always this good, and even now there are nights when it's not great. But I can usually pinpoint behaviors or factors that contributed to a poor night of sleep. As Matthew pointed out at the end of his talk, one major key is consistency. You need a sleep schedule in which you go to bed and wake up at the same time every day, seven days a week. None of this, "I'll catch up on the weekends." I realize this is difficult. For many people, life gets in the way. You owe it to yourself to do anything you can to improve the quality of your sleep.
Rather than repeat what I have previously written about sleep, I'll just link to those posts (channeling @lucjah for a brief moment) in case you want to go down the rabbit hole.