It'll take you anywhere from 1 year to 4 years to get to N1. Realistically probably 2.5 or 3 years on average.
I managed to get N1 1.5 years after starting Japanese, I spent about an hour and a half everyday on anki, and exclusively consumed Japanese media during this time. No grammar guides or textbooks or anything, just endlessly learned more words and bashed my head against the language.
You can read and write like a native, and pronounce like one too. You just need to put in a lot of effort.