It died on the interstate. Took to Jeep. They gave it back. Suggested an electrical specialist. So batt is good. headlights work. Radio works. Checked power at starter relay. Check fusible links leaving starter relay. All good. So what next. Is there a main fuse? No power at ignition.
1) check the battery connections. Take them off, clean them, test the battery itself, connect them, check the harness for power. IF all of that passes (I suspect you'll find something there), then we'd go to the next step. Any of the above could still allow enough power for basic stuff to work but not the vehicle itself.
If you can't take a nano-second to press shift/period/etc. and make proper sentences and paragraphs, I don't know if I can take a few minutes to respond to your topics... It doesn't have to be perfect by any means, but a little effort goes a long way.
I won't claim to be an electrical pro but if the vehicle was running when it died and the other stuff is functioning I wouldn't say it's the battery I would suspect something like the alternator/distributor connections.
Is your jeep factory or do you have any electrical components patched into the system? Winch, snow plow, extra lights, soundsystem?