My son has a 1994 chevy camaro that is starting and idling just fine and after about 10 minutes of idlying it just dies and it won't start up again until it sits for a couple of hours.Can someone help us to try and dianose this problem we're having. We've just changed the fuel filter .

Could be the coil.
Next time it dies, try a burst of starting fluid to verify spark is lost, not fuel.

It's very possible the Ignition Control Module (ICM) and coil packs need replacing:

Ignition Module/Control Unit by ACDelco - Advance Auto Parts

Ignition Coil by ACDelco - Advance Auto Parts

ICMs and coil packs should be replaced every 120,000 miles or 10 years, whichever comes first.