Ok, so you have starter working as I understand it.
Turn the key on, but don't try to start it - do you have fuel pump function (you'll hear a whirr from behind you).
If so, the fuel pump's working. If not, your pump may not be functioning, or the relay box might be toast, or your inertia switch might be tripped or bad, etc.
If you have fuel delivery, you'll need to know how MUCH fuel you're getting, and that means testing the fuel pressure at the schrader valve on the rail.
If pressure's where it should be, move onto fuel & ignition timing. If not, look at the pump or regulator.
If when you try to start it the engine turns but won't fire, check the rpms - if at 0 while cranking, look to the crank position sensor. If it's moving the tach, try holding the gas to the floor while cranking, the engine may be flooded, you might have a bad cam position sensor. Try this repeatedly - if the engine wants to fire but when you lift off the mashed gas pedal it dies, attempt repeatedly. If it fires during one of several attempts using this approach and it stays running on its own, you likely have a bad cam sensor.
