I don't mean for this to sound like I'm being harsh but......
#1. Listen to the advice given above. Especially concerning the "firetrap" part.
#2. You need to do as much reading as you can. Both on here and elsewhere. You have LOTS of info at your disposal. Your reading will answer your questions faster than posting, since you won't have to wait for a response.
#3. The largest leaves on a plant are the ones that collect the most light for your plant to use as energy. This holds true for most of the plants life cycle.

I don't want to sound like a know-it-all. I'm learning too (see the "wannabe" part in my username). But you really do need to read as many "stickys" in this forum and others as you can. One thing worth mentioning: Don't take every single piece of info you read in posts as the pure truth. Most of my reading is done in the "stickys"and e-books, I also watch as many videos as I can find the time for. Stickys are generally reliable since it would take a real dumbass attack, for someone to post bullshit info in a sticky. It would never make it to the point of becoming a "sticky".

Also, if you see something contradictory, just cross-reference it to see which way is generally accepted as the truth.

Sorry for the long post---I just didn't want you to turn to posting to answer ALL of your questions. You'll learn faster by reading. Good Luck.