wiring problem

the fuse box under the hood has some type pf problem.when i go to insert a fuse in the hazard/horn spot or dome spot the slot just burns the fuse up as soon as it touches metal. this also caused my fuse box in the car to short out or something. replacing the fuses didint fix the stuff that stopped working. i have no idea im guessing its a fried wire but i would apreciate your help this is my first toyota.