Those brackets are a really straight forward installation. They use 1 existing factory screw in the wheel well and 2 self tapping screws to secure them.
If you go to the page, https://www.sharptruck.com/truck-hardware-custom-fit-mounting-brackets-gb755006. There is a video showing how this bracket mounts in the wheel well.
If you have a new Ford truck that normally needs no drill brackets, you need to have those as well as the 14" offset brackets. You would install the no drill brackets first and then mount the 14" offset brackets to the no drill brackets. If you do not have a Ford truck you do not need the custom fit brackets.