Looking for some help with light wattage, and intake/exhaust.

Tried postn' some questions on newbie central but didnt get many responses so I'm tryn' my luck here I guess. This is for medicinal use, mostly high cbd counts. To start off, my knowledge of growing anything is very limited. I have been reading the last few weeks thats it. The space Im growing in is my closet and its approx. 3x3x7 in size. (feet). I was forever looking for a solution for to exhaust/intake because I couldnt put a hole in my door and found this which I think should do the trick. http://buymarijuanaseeds.com/community/threads/how-to-one-solution-to-the-doorless-grow-room-issue-pp-zip-door.112082/. Hope that link works. Anyways my two main concerns center around intake/exhaust (making sure Im doing it right) and lighting. At least for right now. I plan on using passive intake at the bottom of the doorway ( panda cloth if you looked at the article) and exhaust in the top right corner. I am going to use an intake fan on the exhaust. To my knowledge you want the exhaust vent as close to the lights as you can to suck the hot air out, and you awnt the intake vents to lead to the plants. Like I said though, Im a super newb at all this so tell me if Im wrong, please. For lighting I plan on using HPS lights for all phases vegging/flowering. I have no idea how much wattage I need for each stage however. And with that wattage shoyuld I didvide it into multiple lights or just one bigger light for each stage. If anybody on here can guide me in the right direction Id be really appreciative. Thanks.
 
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