If the buzzing is caused by RF interference from amps, computers, lights, etc. you need to apply conductive shielding to your guitars' cavities and back of cover plates/pickguard.

You need conductive shielding paint in the cavities, copper foil tape on cover plates and a grounding wire to make it work. The paint and copper tape must connect/touch to so the paint may need to extend out 1/8" or so outside of the cavities.

You may find it easier and about the same cost to have a reputable guitar shop do this for you. Make certain they use good paint like what is sold by StewMac - a lot of cheap paint sold on eBay is ineffective.

You can see an article on conductive shielding at this link >> https://www.artisanluthiers.com/blog/conductive-shielding-guitars/