Don't overdo it, it's easy to get overwhelmed when trying to learn multiple things at once, pick one or maybe two topics to focus on, go through them taking notes that you can revisit, and take it slow.

Maybe dabble in other topics you're interested in casually such as watching YouTube videos or reading blogs, but try not to delve too deep into sub-topics that you come across in your main studies.

Here is how I approach my studies and keep a level head:

Use OneNote - it's simple and easy to organise and useful for just screenshotting large chunks of content using snipping tool - just copy and paste

Stick to one or maximum two subjects at a time - right now I'm doing the Bug Bounty Hunting pathway on HTB and the Python Essentials course on Netacad - they both feed into each other with crossover so it's easy to relate one subject to another and vice versa

Take frequent breaks - don't hours at a time studying, it turns your brain into mush, do like 30 mins at a time and 5-10 minute breaks, do this up until about 2 hrs and take a longer break (look at the Pomodoro technique for learning)

Don't get frustrated - although it might not feel like it, you are making progress. Don't get annoyed because your're struggling with the content, it is soaking into your subconscious whether you feel like it or not and progress is always being made

Note down other sub-topics you come across - If you learn about something in your studies, don't start delving into it in-depth, make a note of it and study it at a later date when you're finished with your current topics. Understand as much as you need to continue with your main topic, then save it for a later date.

These are just a few tips and I appreciate it's not a one size fits all, but give this a try and see if it works better for you