2001 Tahoe LT shut off while driving

[CAP123]

I was driving my 2001 Tahoe 5.3 LT down a gravel road when out of nowhere everything shut off except a few lights on the dash and my radio. All my gauges quit working but the lights on the dash were on. I went to crank it and it didn’t even try to start. I had someone try to jump me and didn’t change anything. I checked the battery cables and they weren’t loose so I pulled them off and only found a little bit of corrosion. I cleaned it off with what I had and still nothing. I checked a lot of fuses and everything looked normal.

Where should I start? I was going to have the battery tested and check ground wires. Is there a chance the security system locked me out?

 

[OBSandaNNBS]

Can you hear the fuel pump attempt to work with key on but not in the start position?

 

[OBSandaNNBS]

I was going to have the battery tested and check ground wires.

This is a good idea, start with fuel pump check.

Is there a chance the security system locked me out?

Possible, but unlikely.

 

[CAP123]

Can you hear the fuel pump attempt to work with key on but not in the start position?

Doesn’t sound like it’s turning on

 

[PG01]

Turn the key on snd off a few times and with it in the start/run position give the gas tank a few raps and see if you hear anything

 

[OBSandaNNBS]

Doesn’t sound like it’s turning on

What @PG01 said.
And if it still cranks but doesn't start, next step would be to check the relay. Your truck should have a fuel pump relay in the fuse box. You can try swapping that with an identical one from another spot. Then try to start.
You also may be able to hear it click when the key goes to Run position.

You can also check for fuel pressure after that before you replace the pump. Just to make sure.

Fuel pumps are known "wear items" from forever ago until at least 2014 I believe.