I want to be a biological oceanographer.

[KajalReed]

Hi, I'm 15, and I'm going to be a sophomore in high school for the 2016-2017 school year. I already know what college I want to go to, and I was planning on getting bachelors of science for oceanography, for masters degree, what should I get my masters in? I want to be a biological oceanographer, but not sure what I  get my future masters degree in. Can you please help me and guide me, it really means a lot. And do any of you guys regret being a oceanographer? And if you could change your profession again would you do it?

[Ben the Donkey]

Marine biology would be an obvious choice. 

I very much doubt you'd regret it if you're into that. I probably would do the same thing if I had my time again. 
When I could fine time between rock concerts, of course. Because obviously I'd be a kickass guitarist as well. 

A quick search online line (I'm in Australia so I don't know ) would probably tell you where to study. If you're in Australia, James Cook in Queensland. You can even go on field trips out to the Great Barrier Reef.

[KajalReed]

Haha, thanks for everything! And sadly no, I'm in the United States, but can't I always do study abroad for James Cook?

[Ben the Donkey]

You could certainly try.
Very popular study area though...  because of the Reef.