how do i get a bolt out

one of the bolts broke off while taking the exaust manifold off in my 2000 grand am gt 3400

remove the head and drill out the bolt. Very sketchy operation though as the head is aluminum and the bolt is steel and it is difficult to drill on center. The bolt is probably stuck due to dissimilar metal corrosion and will not loosen very easily. I would remove the head and soak the remaining portion of the bolt in penetrating fluid for a coupla days before I try anything. If there is some shank left sticking out you may be able to grip it with locking pliars. It is going to be difficult to keep from damaging the threads no matter what you do.

this is a tricky job.

I found that heat will help loosen some of the stuck bolts.
Probly thread locker holding them.

Good Luck drilling them out!