Should I tighten the line to the gas tank with a wrench or just hand tighten?
Who uses plumbers tape?
I assume you mean the POL fitting at the regulator to gas bottle connection, tape isn't required it's a compression fitting modern ones have a rubber seal and can generally be tightened enough by hand. Check with soapy water and don't forget it's a left handed tread
Should I tighten the line to the gas tank with a wrench or just hand tighten?
Who uses plumbers tape?
Install it exactly as you would if it was a gas BBQ at home.