Welcome, Zaks.
I don't know if there is any particular right first step - but I do know opening up and talking about your situation certainly helps. Have you considered Al-Anon meetings? Try a handful, preferably different locations as they all have their own flavor.
Kids adjust to change, probably better than adults do! I wouldn't worry about that change as much as I'd worry about the damage being done by having an alcoholic father in the household. To me - that's the bigger issue here.
I am sorry for your situation that brings you here, but hope you find this forum a safe place to share, learn, and feel a little less sad!
Keep coming back,
~T