Many things wrong with my k10 march

Besides the ugly body rust and a very ugly but aesthetical dent made by some old guy who wasn't looking at the road and bashed his car onto mine exiting a roundabout (thankfully he's going to pay for the damage) my poor march is having a bad luck phase, after that, it started stalling, some blokes got in and stole some of the most insignificant stuff i ever saw some junkie steal from a car, they literally kept the radio, and took a random 8 ball i had in there and some cheap sunglasses, and to worsen the life of my poor poor march, the battery died, today i got a new one, as the car was in a parking meter, and i risked getting fined, and battery in, and...
the car starts but immediately dies. so i'm not a very anxious person, but this car in particular leaves me anxious af, as i love it very much, and i know japanese cars of this era have electrical problems, mainly distributor, but can it be vaccum lines? i read here some cases where this happened and it was vaccum problems or spark problems, but then i open the fuel cap and this loud pressure sound exits as i open the cap, i know here in madeira island the weather is mostly warm and today is particularly hot, but i don't think there should be pressure inside the tank, so can it be fuel lines?