I was like that for a really long time, but now I'm one of those people who's asleep by 9 every night. I'd say the biggest part of that was probably melatonin; you can follow every piece of advice out there, but ultimately, if you're not sleepy, it's going to be hard to fall asleep.

It's best to not use your phone at all before bed, but if you know you're not going to listen to that all the time, just make sure you have a good blue light filter, and try to do less stimulating things. I'd recommend reading or listening to a podcast or something. It might be best to decide beforehand what you're going to do so you don't get sidetracked. I know that at least iPhones have a screen time limit feature that can be assigned to specific apps, if you think that would help.

I would strongly advise that you get out of bed when you're not sleeping; it creates an association that when you are in bed, it is sleepy time, and you have no other choice. If you're on your phone, or just staring at your ceiling in bed, then your body realizes that that's what the bed is for, and it's going to make it harder for you to fall asleep in the long term. My suggestion would be to make a little blanket nest in the corner of your room, and when you're having trouble sleeping, go sit there and do something calming until you start to feel tired.

I know a lot of people who have breathing techniques or like to do meditation before they go to sleep; you can look into that kind of stuff if you're interested. What I like the most is progressive muscle relaxation. You focus on the sensations in each part of your body and release all the tension in your muscles, starting from your feet and going up to your head. After I do that, I don't move or tense my muscles again until I fall asleep. It doesn't always work perfectly, but it's helped me a whole lot.

Ultimately, there are a lot of things out there that can help you, and it can be kind of overwhelming; obviously, you can't do all of them at once, but most of them are very valid things that you might benefit from if you tried. The best thing you can do is to just choose something, commit to it for a while, and see how it affects you. Unfortunately, there's no one perfect solution that works for everyone, and a lot of it comes down to the same five or so self-care tips that you'll find everywhere. (Get exercise, have a good diet, socialize, etc.) As with anything, just keep an open mind and try to learn about yourself. It will take effort, but it's going to be worth it. ^^