My 2000 Chevy Express cranks but won’t start.
Then, clearly, it is broken. That’s the best answer I can give to your 8 word post.
Tell us a bit more. Have you done any troubleshooting yet?
We had a similar problem with 01 express 3500. Would crank and fire but wouldn’t run. Our problem was the passlock sensor in the ignition.
Most likely it is either a no-spark or no-fuel problem. That’s the first objective, figuring out which. Ask your shop to check for a robust visible spark at a spark plug during cranking.
Give it a shot of starting fluid in the intake.
If it starts and runs for a second, it’s a fuel issue.