Why will my cat start but die after I put 1gallon of very old gas in it

Yes I more or less did I put 1 gallon old gas in it when it was close to empty then drove it till the gas light came on and put 5 gallons of regular with an octane booster with it and now it won't start so I put 1 gallon of premium in it plus cleaned the throttle body

so,it's cranking over but not starting..what are you missing? got ignition spark? got fuel? got compression? missing ANY one of these 3? testing has to be done to find out.