1997 5.7L vortec cranks but won't start

I don't know. And I don't know how to check that. I sprayed a little starting fluid in the intake just to see if I could get any sign of life out of it but nothing

Unplug an injector use a test lite put one test lite lead on each terminal crank engine lite should flash, if no recheck fuses and injector relay could also be a bad engine control but you'll need a scanner that can measure injector pulse width or injection freq. or duty cycle to check for sure