The first one is correct. You can also say: I am studying English because I would like to work abroad.

The first sentence is correct: I am studying English because I want to work abroad. Also know that you can phrase this sentence in a different way: I am studying English because I would like to work and study abroad. If you express desire to do something or trying to aim towards a goal you have then it is most appropriate to say: "I would like to" not "I would want to".

The correct phrase is the first one. You can say whether: I want to, or you can say I would like to, for expresing desires but is not correct to say I would want to.