Dancing

hi just wondering if there is anyone who could give me advice on the best style of dancing to study if i wish to pursue a career in musical theatre? I thought that ballet might be of use as well as Jazz, but i am really just guessing. also, if anyone can give me a good website that gives a better run down on how to write a CV that would also be really helpful. I know how to write a CV, I would just like to improve my skills. again sorry if there has already been a post like this. thanks :)