I would highly discourage getting a fire stick, they’ve locked it down so much its just annoying. Yes, you can get there but found it much easier on android tv boxes, specifically the Xiaomi Mii TV ones. Which one you get probably depends on whether you need 4K and/or dolby
My experience has taught me not to ‘apt autoremove’ unless im really sure what they are!
Take it one software at a time. See it’s running fine then move on to another. You’ll often realise something down the line will be helpful so will go back to make changes.
Keep a running list of software and the ports used.
With docker, do not automatically do :latest on important software (nginx proxy manager, SSO software, password database, anything you use regularly, etc). I did that and was burned a few times.
Also that at some point you’ll either mess up or realise it would just be easier and start again with a fresh OS install. Keep copying data (docker compose files and persistent storage) on working software before starting a new one, or before installing anything directly onto the OS, or before major updates.