Carriage bolt rotation
If you have clamping pliers, commonly called Vise-Grips, and you can get some bite on the head of the bolt, a solid grip will enable you to accomplish your objective.

Alternatively, cutting a slot in the head to accept a straight-blade screwdriver will work. If you cannot get to the head side conveniently, cutting a slot in the opposite end may also work. These slotting actions will require a steady hand on a hacksaw or the use of a hobby tool commonly called a Dremel tool, aka rotary cutter or rotary grinder.

Yet another non-destructive option, if the bolt is of sufficient length is to add two nuts to the threaded portion, tighten each one against the other and use a wrench to hold the bolt while turning the other nut as appropriate.