First thing I would do is drain the old fuel out and fill with fresh fuel. If the guage is showing less than 1/4 to close to empty just fill with fresh fuel. Add some fuel cleaner
I would change the plugs those are cheap and easy to do on that truck.
see if there are any codes. If no codes you should be good.
get the truck warmed up well before you go in. Warmed up as in to operating temp 195/210. Some people like to put a lower degree thermostat in the engine to keep the engine temp lower. So make sure they didn’t do that. If the engine temp stays in the 180 range the thermostat is most likely a 180 stat.
air filter and fuel filter. All relatively cheap to replace. Maybe $50 or less if you buy online