Writing off expenses on 1099 forms while working as a w2 employee as well

I work for an electrical company 40 hours a week and do electrical on the work on the side as well. I’m getting 1099 forms from a few customers i did work for this year. Am I able to right off things like business insurance, vehicle registration, or tools costs under these 1099 forms? This is my first year dealing with both so any input would be much appreciated!!