Lennox built in 1988, buzzing, fan not turning on top, fan inside blowing but air not really cooling, checked all breakers are on.

Since it is buzzing, could be a bad start/run capacitor, a bad condenser motor, pitted or bad contactor. I'd go for the condenser first. Match the one on the unit but be sure to shut off all power and discharge the cap by grounding the leads to the condenser frame.

pitted or bad contactor.
I'd go for the bad contactor.