pot with 6 pin

can i use a stereo pot as a mono pot to controll a servomotor

You can,but need to put an
You can,but need to put an arduino in between. There’s an example in Arduino Library called Knob. That will do what you are trying to achieve

Without arduino,you can use timer IC’s to generate pulses,like this one

But if you are trying to control the servo with just one POT,and nothing else,I guess it wont work.