Hello from ON Canada!

I'm brand new to saltwater but I've wanted one since I had freshwater tanks as a kid! I have a 120g aquarium up and running. I'm looking for some thoughts on first fish? Was thinking of Yellowtailed Damsels as a first fish, maybe a group of them say 3-5. Also I wanted 2 clown fish, can you mix the types of clown fish you have in 1 tank, ie a orange and a black? I've heard they may get nasty with different kinds of there own spieces. I'd love to hear any thoughts.