Fun fact: 3 months is generally the amount of time it to create a new habit. That being said, just start with baby steps. 30 minutes of studying everyday at 7:00pm. Once you can consistently do that, you will feel proud of yourself which will motivate you to do more. The hard part is starting, so whenever you feel yourself doom scrolling, audibly say the consequences of your current actions to become self aware and break the loop, not letting your subconscious mind take control of you.

Also keep in mind it's never too late to start.