On the fuel tank once its plumbed in and fuel added will it draw fuel on its own by the vacuum from just driving the truck regardless if a filter is added or not?
No.
Most auxiliary tanks are plumbed in using a 'Tee' installed in the tank filler hose. Several ways to make the system work, easy to more difficult.
And of any of these choices, I would add a 1/4 turn valve at the tank, before any plumbing, in case there are any issues in the future.
1) straight gravity feed, the 'Tee' in the filler hose has a "rollover valve" installed that has a ball that floats when the filler tube is full shutting off the fuel from the auxiliary tank.
2) straight gravity feed controlled by a 'gravity feed' specific 12 volt solenoid
3) electric pump, dash controlled switch
4) electric pump, tied into the trucks fuel level circuit. Typical is the pump cuts in at 1/4 main tank level and cuts out at 3/4 main tank level.
#1 would be isolated with the 1/4 turn valve you install at the tank.
#3 can very easily lead to a fuel spill, no matter how careful you are.
I have #2, has worked well for 7 years now.
If it was me, I would call the shop now and see what method he is installing.