Uphill struggle engine rattle and white smoke coming out from exhaust

I am currently having idling issues. The throttle body was cleaned out a year or so ago as it used to stall when idling but always managed to restart. I have also had the alternator replaced as the car was misfiring. Recently the car started rocking a bit when idling. Now when I go uphill, car seems to struggle and there is a bit of a rattle coming from the engine and white smoke blows out the exhaust pipe.