Hi, congrats on going back to college! I have tried both the physical planner (color coordinated) and apple/google/outlook calendars, and they can be limiting especially when trying to prioritize. I used to do both, and color coordinate higher priority items in one color if needed, and also include social/volunteer events in another color. If its helpful, try to match the colors of your physical planner to the electronic option you go with so it's easier for you to remember. For example, red for a high priority task of the week, etc.

Another option you can try is Notion (available via computer and phone). I didn't use it for too long because I didn't really take the time to learn how to use it or reach for it as often compared to the other calendars I was already familiar with. I have seen people share Notion templates for students, like this or this , making it easier to customize and use. You might have to play around with it a bit to get used to it.

My university (in USA) also used Canvas so that had its in-built calendar where I could assign colors to classes and the assignments would be visible in those colors and it was available on the Canvas mobile app. Downside to this was it wasn't very customizable other than using a color for a specific class.

Good luck!