99 blazer with no compression in all 6 cylinders

The timing is off. You should look at the timing belt and make sure that is ok. A bad head gasket and cause LOW compression, but NO compression is timing related.

Ok, also I was told maybe the distributor might be slightly off, could that be a possibility ?

zero compression in all cylinders would likely be cam timing, it may be the timing chain jumped. To have 0 compression across the board means the intake and exhaust valves are out of sequence or something is preventing them from closing completely. I would first however open the valve cover and make sure the valves are opening and closing when they should. Compare the new pushrods to the old ones, valve stems, springs, etc. The distributor being misaligned will throw off spark, but the engine would still make compression.

Ok, I removed the valve cover on the driver side, and the valves are opening and closing.

I went ahead and removed the distributor and set the motor to top dead center.made sure the lines matched up. Re installed the distributor so it waa firing on the first cylinder. Put it all back together. It sound a little better. Now It sounds like I'm getting compression on a couple cylinders.