The ignition switch is wired incorrectly, is damaged,or a wire is damaged and contacting the starter relay circuit .
depends on year try it and see
Try having the alternator checked at a local parts house, off the truck and on. If it tests good on a bench tester, then bad on truck, then you might have a bad voltage regulator or wiring problem. If it's an older ford, (should be if it's a 100), then the regulator should be separate from the alternator.
Low battery.
That's not a question. Try asking"Why won't my ford escort start?"
you should try to poo in it
Try a Ford Ranger pickup. Any F100 frame will be too wide to fit the tires under the fenders. A common swap is an S10 frame.
To find accessories to decorate a Ford truck can be found at Auto Zone, Napa or any local auto parts store. You may also try Ebay or Amazon.
try timing belt
From the research I've done, walmart does not sell truck covers for Ford F150 trucks, however you may want to try www.truckcoversdirect.com or www.empiretruckcovers.com as they have the products you are searching for.
Try graphite or lock lubricant
Try replacing the fuel pump.
It depends, you could try starter fluid.