Fiat 147 goes out

Hello, a greeting for two I am Mauro, from Balcarce, I have a Fiat 147 Cl5 of 83 , I tell you, the car was fine but now that we are in quarantine it left it standing like 3 weeks out there, and this happens, I describe it that way, although much of mechanics I do not know:

* I turn it on and after a while the car and the panel goes out, but the position lights and the low lights are still set.
* Being ahead, it threatens to go out but does not go out.
* The battery has an indicator that says if the battery is green, and the indicator is green.
* Also notice that it goes out as if I turned it off does not make any noise of anything.
* The car does not long no smoke through the pipe, and changes the spark plugs and cables 2 months ago x there.
* Today I turn it off and I wanted to start it and just start after trying 11 times.
* Does not lose any fluid.
* The car is as original as possible, it is not touched or anything.

If they could help me or give any clue that it may be barbaric! Greetings for all!