Do you think it is more beneficial to take a small course on a language say Spanish, just enough to learn basics, and then learn through immersion by taking an English from Spanish course?
Given the way Duolingo is currently set up, quite possibly, yes. I've been working on Ukrainian and Dutch this way of late, and it's been greatly beneficial. Learning a language this way has you typing ever so much more in it, which greatly aids retention and understanding. Note that this assumes you use the website. The apps don't tend to work as well in reverse.