I have power coming from the fuse panel box to several lights an switches but they don't work. There are also other lights on the same breaker that work. Still power running to the switches that don't work.

How did you confirm "Still power running to the switches that don't work"

I used a pen power tester

I don't know if the power is back feedint the panel or how to find out.they used to work then out of nowhere they stopped working for no reason. I checked the panel box, everything seems to be in order an the switches. I thought there might be a break in the line but I still have power to the switches an lights

Could be a loose neutral somewhere.