Afteri drive my 1991 nissan stanza for about20 minuites and i turn it off it wont start again untili let it cool down then it will jst start rite up

if turns over and no fuel the filter might have plugged from running it empty needs replacing and how much gas did u put in it and did u recycle the key to pressurize system

That sounds like an ignition coil problem. If that model uses an ignition coil (not electronic ignition), it probably needs to be replaced.

Have you tested the Flashers for continuity?

Check fuel pressure. Pump may be failing.

Smoke under the passenger side can be due to clutch wearing but since the car refused to start it seems that there is a fault in the fuel line. you need to check the fuel flow if there is fuel in the tank, check the ignition system for voltage before we can go further. Also you mentioned leak but not described the content.
Please check this out and clarify.

Nissan recommends only NGK ZFR5E-11 spark plugs for your 1991 Stanza and they already come pre-gapped in the box. They might cost a little more than bargain brand spark plugs, but your stanza will definitely run much better with OEM plugs.

your head gasket is gone

its called a neutral saftey switch and yes, if it goes bad it will prevent the car from starting.

Then it is either dirty or loose battery cables, or the fusible link in your positve cable, or the ground cable is not grounding.

The radiator cracked on my 1990 Nissan Stanza. I had to replace it.