I still am fairly new to Tera. I have t upgraded anything past +6 yet.. Now for going to +7 is there any special armor rarity I need or anything just like +6?

well first off, after +6 you'll need to start using a different kind of alkakest, the refined kind in order to get your equipments +7~+9 and the chances will be better if you use rarer items to enchant with. Some say that if you used enchanted items to enchant your gear, the chances are higher, but I myself havne't seen the different, Just use the gold fodder and maybe the blue fodder, I don't suggest the use of white fodder after +6 due to the cost of the refined alkakests.

Okay and what about after +9 to masterwork through 12 what kind of alk is that?

Masterwork alkahests? lol

Cross your fingers and hope the RNG gods smile upon you.

If you're not in t13-t14, don't go above +6, you can spend the money you'd spend +7-+9ing t12 buying t13 or +7-+9ing t13 to buy t14. +1-+6 costs nothing so it's always better to go up a tier rather than going into refined alka on lower tiers.

Yeah, this i know i'm not going over +6 until i hit t13.