Truck runs then shuts off?

Hello, have you checked it for any codes stored in the PCM? It sounds like its running out of gas(fuel pressure). It looks like, from the video the check engine light is staying on. The PCM wiring diagrams show a Fuel Rail Pressure/Temperature sensor, so you could see if its running low on fuel pressure right from scan tool data. Thats where I would start. If you can get it to AutoZone or another local parts store, they should be able to scan it for codes, but it really does sound like its just running out of gas with the way its stalling out.
There should also be a fuel pressure test port on the fuel rail, it has a small plastic cap on it then you'll need a fuel pressure kit to check if it losing pressure. I have seen these with a bad check valve in the fuel pump as well, not hold pressure once the key is Off. Has the fuel filter ever been changed?

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

There should be a fuel filter on the frame rail, but if its never been changed then the pump may have failed by this point. If you find the small pressure test port on the fuel rail, you can buy a pressure test kit for pretty cheap from Harbor freight, it comes with the small Ford fuel rail adapter, they are the most common in these kits. Just pull the fuel pump relay or unplug the inertia switch on the passenger side kick panel, let it run down on fuel pressure just to be sure, put a rag around the port and screw the adapter on. You should have about 45psi of pressure with the key On and it should hold that pressure for awhile. It might get up to 40psi roughly, but then when started you might see it drop right off. It has pretty high mileage, so this is when issues will start to show up unfortunately.