1988 Toyota Truck HELP!

I just bought a 1988 Toyota truck, 4x4, AT, V-6 with 255,000. It has been parked for almost two years.
Nothing has been done yet. (New gas, plugs, etc.)

Where Do I Start?

Could the gas be bad, plugs, fuel pump/filter?

The truck will crank but only if I give it gas. When I let off of the gas it dies.

There is also a loud clicking noise coming from the engine. Increase in RPM = faster and louder noise but as the RPM's decrease the noise will go away until back around idle speed.

Any help will be SUPER HELPFULL