2002 Chevy Cavalier

Could be the clutch hydraulic system. Check clutch MC fluid level, if low you may have a leak in the system. You would have to inspect the system for leaks.
If full, then bleed the slave cylinder. Have someone push in clutch pedal, observe slave rod, movement should be smooth and about 1".

If hydraulic system checks out, then the clutch may be worn out and would need to be replaced.