i was setting it and i was just wondering how much vacuum i should get with a l98 with a stock cam.

Probably around 20-22" at 800RPM idle in park, or thereabouts.

ok right now it stays at 15 and says late ignition timing on the gauge does late mean too much or not enough?

Late means too little timing.
I wouldn't just trust what your vacuum gauge says as far as advice, but it's a good start.
What's your timing at that point, and idle speed?

well back when i set the timing it was at like 1800 rpms so im sure the timing is wrong i bought a timing light today and tommarow when i go back to my work ill mess with the car.