Linux

Congrats on switching to Linux! There's a lot to learn, but this also means you get control. Furthermore, what you learn is very likely to be useful for a very long time. If you still feel intimidated by the Unix command line I strongly recommend addressing that asap. It's where the magic happens when things go wrong. It can become a super power as well in terms of automating tasks and customization. Look for guides in the format you prefer and most importantly play around with what you learn.

As for your immediate need with the Bluetooth keyboard... OK for real I'm writing this right now from a living room TV Linux (Mint) PC and I've ditched my previous Bluetooth keyboard for a keyboard with a 2.4ghz USB dongle. I've had sporadic issues with Bluetooth on Windows in the past, I've had less (but not none) on Linux, and I just feel keyboard/mouse are devices that are too critical to pass through Bluetooth. Wireless USB is just so much more stable. Furthermore if/when you'll want to log into you UEFI/BIOS it'll be really awkward because such a basic environment has no Bluetooth. I understand this may be of little help if you've got a keyboard you love.