I am VERY new to the bass. I figured that I have some time during this pandemic, so why not learn something new.
Flats will indeed add tension to your neck, which means a truss rod adjustment is probably in order. Dong a truss rod adjustment isn't a tough thing, but I think it'd be a good idea to have someone who knows what they're doing at least show you how to do it the first time - you need feeler gauges and a bit of special knowledge to really do it right.
you can do this, OP! and since you like the "technical" stuff you probably could learn what you need from the internet, but: if you told a tech/luthier "i'd like you to teach me how to do a setup (or adjust a truss rod)" you'd get an 'immersion' not available on youtube. also: you'd get to ask questions and learn about your specific ax in case there are peculiarities. TBH: that's how i learned so i'm favoring my own experience on this. once you get some concepts = youtube is your friend! good luck with your great looking instrument!