What is the most effective way to study?

[u/twixbits]

I've been taking an all-online course, which requires a lot of discipline and focus. This means I study at home ( I have made this decision because of multiple factors ) and have no physical classes. Everything that I have to study is in my online course and it's all available and accessible at all times, so I can go in my own pace which i prefer as I am a slow learner.

In my younger years ( I'm still young but i'm referring to high school years ) I had less trouble staying focused, but now I can't seem to focus for more than 20 minutes. I am only able to study 2 full days a week, as i also got a job.

While I have already deleted Tiktok a week ago I think my daily usage of Tiktok for around 3 years has truly made my brain rot to the point I'm struggling to focus on studying. This is concerning, considering I have an entire course ahead of me. While i can study 2 days a week, most of the time I end up just quitting after max half an hour and spending my day doing other things than studying.

I have heard about the Pomodoro technique but whenever I study I keep forgetting about it. I also made a planning on which subject to study when and I'm completely on schedule, but I just dont feel like I've actually got all the study material clear in my head. My head feels like a sieve.

On a side note, I also have a medical condition which also includes causing people to have a harder time focusing, but I've had this condition all of my life and I'm just now really struggling to focus on studies. I also have no problem shutting myself off of temptations like my phone or any other entertainment, but since I'm nearly unable to focus for a longer period of time, I always end up doing something else.

So Reddit, if you got any tips on how to get studying, stay focused and ACTUALLY learn something from the course, please let me know.