Rooting is pretty easy and straight forward now days. Use payload extractor to extract system image, use magisk to patch boot img, then fastboot flash patched boot img, and install magisk app.
Unlocking the boot loader is another issue. Not all phones can be unlocked and without an unlocked boot loader flashing a new rom on the phone can be challenging to say the least. Not always though. I would recommend just using MicroG for Lineage OS. No jewgle and it's compatability list is twice that of any other OS out there. Or you can just install Lineage OS which is compatible with most devices and remove jewgle yourself and add MicroG via magisk.
From there if you wanted to try other OSs without fully installing them you can look into GSI (generic system image) roms. Using a tool called DSU Loader you can boot GSIs without fully installing them and wiping your phone. Whatever you do make sure you do your research first so you don't end up with a brick. Good luck!
XDA forums (xdaforums.com) is a good place to look for info on this subject.
Thanks. I've been lurking xda for a couple years now; most of their stuff is out of my wheelhouse but I use the bits I need and can use periodically.
I knew about the system image but didn't know how to obtain that; thanks for the info regarding an extractor. The device I'm going try out is a spare free pixel, so it's fairly ubiquitous for stock images and apps.
Thanks for the quick tutorial, I wish more Poalers shared their knowledge with each other!