I was coming home late and i noticed weird squiking sound. Then chg light came on.
First of all it is three in the morning and i was just few minutes from home.
So i just drove carefully as possible.
Then there was puff of smoke just a light before home.
Now i am extremely scared thinking something blew up but car was moving fine.
I hurried home park and open the hood.
And i noticed two things.
First belt is completely broken off.
Second fan is not turning at all.
Now i am really concerned.
If it is just the v belt issue i think i can fix it.
But i always thought fan would be turning straight from the engine.
It was not moving as if it comepletely seized up.
Like i said car was driving normal as far as i can tell.
Please help me.
I cant lose my datsun

the fan, the alternator and the water pump run off the belt. replace the belt.
also make sure that all the pulleys are in line and that the fan and alternator spin freely. if either feel clunky to turn the you may have bigger problems.

Good advice

I just worked on a car today where the belt came off. It looked undamaged so I put it back on and tensioned it properly. I had a car that would throw a belt about once a year ...

If you can not turn your fan by hand with the belt off, your water pump is seized. This would be the reason that it spat the belt and also explains the noise. The belt being off is the reason why your charge light is on ( alternator not turning ). I'm confused about the puff of smoke.

Replace the pump and belt. This is simple enough so don't stress too much.