If the age on your profile is right, you are a long way away from university, so you have time to learn enough to not need to take Japanese courses, but that depends on how serious you are about it.
I'd recommend you to start with grammar, there's no point to knowing lots of words if you can't string together a sentence. At the same time as grammar, learn hiragana and katakana, right after that kanji. Learning kanji is a pain in the arse but you won't be able to read anything without them.
For grammar I recommend Tae Kim's grammar guide:
http://www.guidetojapanese.org/learn/grammar
As for kanji, there are different methods, some recommend Heisig's Remembering the Kanji, which will teach you how to write them and a basic meaning without the reading. This is good if you want to learn systematically.
I personally prefer learning kanji from real literature and games, as it gives you context and more clues to remember them by. I'm now editing a video explaining how to practice reading Japanese with visual novels. I'll post that here in the feeds when I'm finished.
September 23, 2016 at 11:31pm