Mazda 323 Running Rough, Starting & Power Loss Problems

I need to know the problem in this scenario

Hi, my car was making a screeching sound for a while and then it would not start. I managed to get the breakdown gentleman to tighten the belt which stopped the screech (not sure this is a permanent fix as he only did the top one and said I...

tried to start car today, and for the first time ever the car started without fully turning key i.e when lights and radio should come on the car started up but with a very loud straining unusal noise from engine, not wanting to drive it, co...