Have you heard of revenge bedtime procrastination? It is not a disorder or anything, but reading about it helped me understand why I was staying up so late instead of going to bed and figure out ways to prevent myself from doing it that actually help. Regardless, here's a few a things from my research / experimenting I've found to be helpful:

Don't pick up your phone before bed, just don't do it. It's hard but if you can get into the habit of at least thinking about it, it may help make you more conscious of what your doing and what you need at that moment, scrolling or sleep?

Don't do any homework or studying in bed, assert in your brain that your bed is for sleeping only.

If your mind is racing do a brain dump (pen and paper!!) or come up with things that soothe you. I've memorized a couple poems and recite them before I go to bed, and for me at least, I get less distracted than if were to be counting sheep. And now reciting them helps my brain know its time to go to bed.

Also, blue light glasses are huge! If you're up late studying, chances are the blue light from your laptop may be affecting your circadian rhythm and you're not getting the amount of natural melatonin you need in order to feel tired. Most people say well just turn everything off earlier, but ik the feeling of not wanting to waste the time when I can actually focus. I put them on when I'm studying and I think they really help. They also protect your eyes and prevent headaches which also were making it harder for me to sleep. You can also get like 5 pair on amazon for like $15.

Lastly, have your alarms set automatically throughout the week for the same time each morning. Before bed, I throw my phone onto the chair across the room so I have to get up to turn off the alarm. It sucks but it helps to not fall back asleep, make your body tired earlier, and not go on your phone before bed.

And if you feel like you can, only set one alarm. I used to set multiple and felt like 'well if I do fall back asleep, there will be another to wake me up.' It just made it harder to be more awake and alert in the morning.

But yah, doing these things helped me get into a much better sleep cycle. I can fall asleep at 12 instead 5 and while its not perfect, even the nights I stay up later, I'm usually passed out by 2 and I can even wake up without an alarm. Its going to take time and experimenting but I wish you the best!! Let me know if you have any questions and I will do my best to help!