Does anyone know if there is a way to limit people who join a server based on their level?
No there is no way. Level doesnt mean much anyway.
I’m afraid there isn’t a way of having level specific servers on bf1.
Just be aware though that player level isn’t a direct indication of their skill in BF, A higher level just means more time played really.
So knowing the maps and having all the weapons and sevice achievement perks that people over level 100 have isn’t an advantage?
It doesn’t matter on console because on PS4 you can create a brand new level 0 BF soldier on a new account and use your main account’s PS+ and BF1 to play so being level 0 or another low level doens’t mean this guy isn’t a BF1 veteran.
Knowing the maps helps of course,but there arent any secret routes etc. You can only use 1 weapon at a time and late unlucks arent really better then starter weapons. Perks are a small thing,the default ones are pretty good,the only new one i really like is the smoke for medic. Flak,faster regen i use all the time…
Inconspicuous has saved my rear lots of times when I’m on a hotly contested flag. Gives my squad enough time to spawn on me
I guess I’ll buy a book
about Battlefield1? 
No point. The best lessons are hard learned and given the current (lack of) matchmaking, you will get frustrated, but learn things from better players.
Just don’t play scout. Too many as there is and high scout count costs games. Plus, most of the scouts suck. I recommend medic (can self heal), or support.
Medic guns suck the most. Give medics a shotty
Locking due to necro.