More specificaly im gonna do a metzger son, hes gonna be a tough mutha who will ruin any ones life if theres something in it for him, just like his father would. He saw his dad getting richer and richer aswell as hes downfall when the NCR took over.
He was lucky and managed to get away from california as he saw the republic expand fast. He went west as he heard of the strip, lands with no owner, the khans(he once meet them when they where in vault 15 and liked what he saw) and most importantly caesars legion, a slaver nation.
He will start by helping caesars legion as everyone would tell him that they were a powerfull nation of slaves, slavers and mauraders. He will help them until he gets to talk to caesar about his legion and then he will understand that he aims at rebuilding society and not profiting from slaver trading.
At this point he will tell caesar hes done working for him and start working for independence cuz if theres no law then most people are easier to rob and enslave!

What i ask you is:
-What guns would he use (thinking about the riot shoty and lil devil and please give me at least one shoty for him to use)
-What would he wear (probably something that would cover his face cuz afterall his father was a very powerfull slaver)
-His allignecies (thinking about uniting cookes powder gangers with the khans and becoming the master of both gangs! Thinking about shoooting NCR on sight aswell)
-His name (something as badass as metzger)

Hmm.. I'd say he could use some sort of shotgun, wear leather armor(or reinforced one) with a legionaire recruit helmet. Allegiances to gangs like Powder gangers and such(if he indeed wants to rob and enslave). A name, a name... Dekker?

Legion may do slavery but they don't seem to like personal initiative and they would take over your business so I agree with the notion that your character would betray them later. I recommend siding with Yes Man if you're feeling ambitious, House if you just want a place under the sun. Help Powder Gangers, they are your main allies. Khans are okay too, basically a divide and conquer situation where you destroy big and powerful factions (BoS, NCR...) and support small, decentralized units (Powders, Khans, Followers) that may be useful in the future.

Preety much yeah. Not so sure about helping the followers, maybe helping them up to the point where they think im trustable and then find a way to limitate their influence(maybe kill ONLY jule and let the rest root with no leadership).
In situations like the NCRs power plant electricity distribution should i help everyone cuz i plan on taking everything later on or send power to already strong locations? Or matbe keep everything for me and just me?

Activate ARCHIMEDES and wipe out the NCR, or overload the power plant.