Any tips for Indonesian
If you're a native speaker or just know a lot, there anything I should learn first or anything to help me along the way? It could be with the language or culture (because I'm very interested in new cultures).
Duolingo is fine for the basics. However, if you want to visit Indonesia, you should pay attention to the informal language: it is the actual way we speak and many of the words and verb usage will sound weird to the "formal language". But if you speak to us in the formal language, we'd be glad to know it and we'd maybe even try to use simpler words to you.
. . . I can't think of any more things . . .
I just started indonesian with DL but the total lack of grammar explanation makes it extremely difficult to follow. You are basically just parroting basic sentences without even knowing why. I guess you're better off learning Indonesian from youtube or other sources. There are some very good webpages dedicated to it. This doesn't apply to european languages, at least the grammar seems more accessible to me, so DL is a good companion app.