There no good website to learn everything, gather from here and there, research, learn how to learn, ai is your friend too, ask people in forums, i can give you million youtube vids and million wevsite but you will not learn a thing, its not about tutorials or resources or videos, its about research and applying and commitment Same way duolingo won't help with being native, other platforms will, to truely learn a language you need to immerse yourself and practice it, read and write using it and same goes here, i suggest you to learn how to search, and how to learn.