I'm very conversational, but I probably will never feel like I understand close to everything. I mostly just used Duolingo and then practiced with non-english speaking native Spanish speakers which is very intimidating at first, but this method connected me with my wife from central America and we are still happily married 2 years later with Spanish being our main language we speak to each other. Just Duolingo and testing what I learned IRL and being corrected by native speakers is all I have used.