Problems with my 1995 nissan maxima

I overpaid for it, have had it 4 mths and already replaced alterntor&battery.Now i get steam or smoke from under hood. My fluid are all full and its not running hot. any ideas?

Odor of steam or smoke?

as i said my radiator was full of h2o/antifreeze. temp guage didn’t read hot but a steamy bluish smoke came from under hood up front of car closer to windshield. i only had to drive it 5 min. before it happens. reckon it could be valve cover or similar.