Does collision coverage insurance pay medical bills?

No. Collision coverage pays for the physical damage to your own car, subject to any deductible.

Medicals are paid by a separate coverage-sometimes called Personal Injury Protection, but it may be called by a different name depending upon the State involved. It is what is generically called No Fault coverage. It pays a percentage of your medicals and lost wages if you are infured in an auto collision irrespective of fault. As such, it is a form of "first party" coverage that you maintain on yourself.