so this is going to sound like I'm an idiot but I'm really just new to all of this.
when i went to change the valve cover gaskets i took the distributor out and did not properly put it back it took me a while to realize this but when i did and set the car to TDC it would start and then rapidly decline in RPM and die however two teeth after TDC i can get the car to start if the distributor is turned all the way to the left but if i don't center it shortly after starting it, it dies it is also burning rich at first. any idea where i need to go with this?

Best bet: Start from zero.

Pull the FSM at nissanservicemanual.com and follow the timing instructions from the very beginning...