You can attach both a rack and fenders with the same bolt around the rear drop out. You are also going to need some attachment point somewhere near the seat post; usually these are near the top of your seat stays. If there is no mounting point there, you could get something like this to add a mounting point around the seat post: https://www.amazon.com/M-Wave-Seatpost-Clamp-Rack-Mounts/dp/B0775L5KTZ. Note that you need to find the right size clamp for your bicycle.