I spent 18 months learning Japanese hardcore (still learning it softcore now that I live in Japan).
There are many SRS around and many are free. The one I recommend to most people is Mnemosyne. I use it myself.
Learn to read aloud 10,000 Japanese sentences.
Do not: learn individual words. Learn sentences.
Do not: translate sentences. Understand them instead.
Do not: learn grammar rules. Do get a feel for grammar, do read about grammar if you feel like it, but learning grammar rules in order to use a language is like learning quantum physics in order to drive a car. Sure, grammar rules are the rules of a language like quantum physics is the rules of the physical world. But it’s not practical.
Imperfect finish > perfect imagined
Salam Curhat Berkhasiat 🙂