Alright guys
The other day i was driving back from a mates house, and my car died on me. Upon inspection, my fuel feeder had popped out, so i placed that back. Once, i done that the car wouldnt start, being me, i thought it could be something ill never be able to fix. So i called the RAC, turned out it was my negative terminal on battery which was a bit loose

. He advised me to change it as it was rotting, also told me about my starter solenoid, was a bit corroded but, told me this shouldnt affect the car starting up.
The next day i sorted out my fuel feed properly, made sure it was secure. I managed to source another neagtive terminal lead with the earth attached from another mk2. when i attached this, the car doesnt seem to start! ive got electricity, the lights, radio work etc. however, when i try n start the car it just doesnt want to. The battery is about a month old. and it recently had been serviced.
Can u guys advise me on the problem? im no mechanic but, i dont mind getting my hands dirty and know some basics.
Cheers