1995 jimmy it blows a fuse when right turn signal is turned on or you press on brake pedal it blows a fuse left turn signal works and marker lights work need help?

Examine the right rear brake light bulb and socket. The bulb could be jammed in the wrong way causing a short. If the bulb and socket look ok check wiring in back leading to the right rear light, it may be pinched or damaged. If the truck has a trailer plug connection check the connections and wiring leading to plug for damage.