Car will not start

Does the key have a chip in it? If so, then look at the security system as the possible cause. I'd start with attempting the "relearn" procedure. With this procedure, the car's control module will learn to accept the key's resistance/code and start the car. It's a tedious process, but it's the best (freest) place to start. If it doesn't take the first time through, try it once or twice more before moving on. --> https://sep.yimg.com/ty/cdn/yhst-21854666697846/gm-install-and-key-relearn-instructions-final.pdf

If that doesn't work, the next thing to do would be to take the key to the dealership and have them check it. It should be free to have them check it, but might be a few bucks. Well worth it. If it's bad, then get a new key cut and coded right there. Go home, and do the relearn procedure for the new key.

Start there and let me know what happens. We'll go from there if necessary.

Have you checked the key and security system? Does the key have a chip in it like the one pictured below? If so, then you have to check into the security system. If there's a problem there, then the immobilizer in the body control module will keep it from doing anything.

Okay. So since there's no security system, diagnosis ought to be simple enough. The next thing I'd do is take my multi-meter, connect the red (positive) lead to the starter wire, and connect the black (negative) test lead to the battery or a good grounding spot. Then have a helper turn the key while you observe the meter. One of the wires ought to be energized if the relays and such are good. If you get 12 volts, then the problem is the starter. If you don't, then we need to look a little more.

Also, check this guide out - it has some pretty good idea in it - https://www.2carpros.com/articles/starter-not-working-repair - I'm a fan of the simple test that they have the for the neutral safety switch. It's easy and free to check, and this is a common problem somewhat.

Start with the neutral safety switch test and then go through the other suggestions and let me know what you find. Good luck and let us know what you find. We'll go from there.

Also, here's the layout of the passenger side under the hood fuse box. Check #17. It'd be nice if it were that simple.