Did you range the transmission selector lever from Park to Neutral then wiggle it while twisting the key? Before you go to war?
If you have power to the big cable stud, twist the key but get no power to the #8 solenoid S stud, the neutral safety switch, or afternmarket solenoid booster relay or ignition switch is not passing current.
If the big stud and little stud both light up a test probe with the key twisted the starter has to be removed.
Once the starter is out laying on the ground take a sharp object and index-scratch a mark in the motor end cap and starter main body.
Use a 3/8" wrench to remove the bolt and stud. The entire stud may come out including it's nut.
It's time to look inside and check the length of the brushes as they sit plastered against the segmented commutator. There should be a healthy 1/4" or more brush length showing between the brush holder arm and the surface of the commutator. If the brush is long enough, grab a screwdriver.
Insert the screwdriver under the brush swing arm and lift it. When released if the brush arm spring does not smack the brush back against the commutator, gooky carbon residue has gummed up the brush pin and spring. Grab a can of Brake Kleene and spray the brush until the spring can smack the brush against the commutator. Repeat for the other 3 brushes.
Is the bronze sleeve bushing in the end cap dry? Smear a smootch of grease into it.
Replace the end up and align with the mark you made. Those long bolts are easier to align with distant holes if you stand the starter up on it's nose. Let gravity help not hinder.
Test the starter on the ground using jumper cables. If it engages the starter is going to twitch - be ready for it.
Don't try to resurrect the dead. Very short brushes need to be replaced, the commutator passed through a growler, bushings on both ends replaced, the starter drive renewed and a new solenoid fitted. Imagine doing this while freezing rain pounds down. Just a month after you installed that Lifetime Warranty El Scumbag special. They'll give you a replacement, then maybe smile as you receive the 5th, the ninth starter. whatever it takes. Aren't so very glad you saved thirty dollars?