I decided I was gonna fix my car back up this year after i accidentally drove into a accident already on the road last year. Passenger axle dropped. Reinforcement against radiator cause a leak. Also power steering line pulled off then it drained. So this morning I decided to jump start the car which wasn't probably the best idea idk. White smoke came up from the back of the engine. Any clues too which one of my problems it can be **** feels like a loss after I seen that smoke. Car has been sitting for 3months btw.

 

Leak in the rear of engine is probably the plastic union at the heater core line. Its literally a plastic piece holding two hoses together. Pull it out and replace with an aluminum union. Probably just a coincidence that it started leaking with your other issues...