The only things that can really cause problems with newcomers to pc building are inserting the CPU the wrong way (although the processor and the motherboard have little triangles to tell you what side it fits) and the thing that still trips me up on the odd occasion of getting all the front panel connectors the right way (ie the power and reset switch and the LEDs since the little plugs are polarity sensitive so if you put them on wrong your lights won't work)
Also make sure that you seat the ram in the sockets properly, I've gotten a few computers that weren't working because the ram wasn't in the slot properly so they just gave em away
Nah it'd be better if I learn it all myself so I don't need to rely on other things later on.
Which I have and I understand most of it now.
It'll definitely fit since my motherboard takes m.2 and type 2280 (which is the SSD I have).