Will not start

Can you clarify what exactly the engine is doing when you turn the key? Is the engine turning over but not starting or is it not turning over at all? Maybe get a video of this because that will get us on the same page as to what you are seeing.

We need three things to start the engine. Fuel, spark at the right time, and compression. Here is a video that will help with this however, we need to start with confirming fuel and spark. Remove a spark plug and hold it against the block and crank the engine and make sure there is spark. Then use starter fluid in the intake to see if the engine fires for a second or two in order to confirm a fuel issue.

https://youtu.be/dCjmRL3p4Cs

Lastly, did you put in good clean fuel if this was sitting? If not, we need to do that first and foremost. Let us know and we can go from there. Thanks

We put clean gas in it when we changed the tank and my dad said that it's getting fuel to the rails, but it's not enough to get it to run. so there might be a clog somewhere in the injectors.

Awesome. That is most likely due to rusty injector pintle causing the fuel to go through the return and not into the cylinder. Spraying starter fluid in the intake will confirm this. If you have it at the rail and starter fluid helps it get starter just confirms it is not getting into the cylinder.

If it were me, I would just go ahead and replace the injectors if this has been sitting.

https://www.2carpros.com/articles/how-to-replace-a-fuel-injector