Car won't turn on, has power

Hi, My 1995 Ford Taurus 3.0 cut off on me the other day on the highway. Tried to restart but wouldn't turn over. Have it towed home and gave it a jump and it works. 10 minutes later same thing just shuts off and all I can here is the fan behind the radiator. Took the battery to autozone and got it tested it passed and got charged some more. Try it again it starts and same as before it shuts off again after a bit of idling. And it sounds like it wants to but it won't. The first time I had it towed when I was turning it on all the lights dimmed severely and the dummy bell sounded like it was dying to say the least that's why we jumped it. I'm guessing electrical. My brother told me to run it and remove the battery so we did car stayed on but lights and everything look like the were fluctuating or struggling. What could be going on? My battery light on my dash keeps flashing and going solid on but when I shift into drive it turns off and flashes here and there.