Anti-theft and gas pump

Welcome to 2CarPros. Yes the anti-theft shuts the fuel pump off. What does the light do when you turn the key to run? Flash or stay on solid? If it flashes the system isn't recognizing the key, if it is staying on solid there is a problem in the PATS system itself.
If you have a second key that worked in the truck before you can try it. Much beyond this you need a factory level scan tool that can talk to the various modules to see which ones are not working correctly. There isn't much else that can be done without the scan tool.