If the jumper cables are both attached to the truck's battery cable clamps; this sounds like the cables and/or the battery posts are corroded on their contact surfaces, and/or the clamp bolts are not tightened on the battery posts. The corrosion that builds up between battery posts and cable clamps often cannot be seen by eye; but it will prevent the truck from running unless it is scraped off both surfaces, preferably with a tapered reamer type battery cable service tool, or with a round file. There should be a shiny surface on the contact faces when they are properly cleaned. If the cable clamps are the aftermarket type; in which the cable is attached with 2 bolts and a strap to the clamp; corrosion can set up in that connection, so all the parts should be disassembled and thoroughly scraped and polished clean.
A battery cannot be tested by just measuring its voltage with a voltmeter. A nearly dead battery will still read close to 12 volts. If you put a good battery in the truck without jumper cables and turn the headlights on; they will be bright; and when you turn the key to the starting position; the headlights will stay bright. If the headlights dim down or go out; the battery is not strong enough to start the truck.
If you are connecting the jumper cables to the starter solenoid and to ground; there is probably a blown fusible link or fuse in the power circuit between the positive battery terminal and the ignition switch.
If you want to post additional feedback by clicking the "answer this question" button; please also include the brand, year, model, transmission type, and engine size in your truck. All trucks do not have the same parts on them, and we can't give you detailed advice unless we know what kind of vehicle this is.