I have this old entry level Fuji that I don't ride anymore, and I thought it might be a nice platform to start trying out some of the stuff I've seen on YouTube. Also, this will be my first foray into building/upgrading bikes on my own, so any pitfalls to watch out for would be great.

The bike currently has an 8-speed Claris on it with rim brakes. I was thinking of upgrading to an 11-speed. Looking at either Sensah or Ltwoo. I can't tell from AliExpress which are mechanical and which are hydraulic. So, I need help figuring that out.

Also, do I need to upgrade the cranks/chainrings? It seems like I probably would. If so, how do I figure out what kind of bottom bracket I need to get?