Learn hiragana and katakana before anything else

Japanese is written with three scripts. Hiragana and katakana are alphabets of sounds, with 46 basic characters each. Kanji are the characters borrowed from Chinese, and there are thousands of them. Beginners often want to start with kanji because they look like the real thing. Start with the two alphabets instead.

Why they come first

Every textbook, every JLPT paper and every beginner lesson is written in hiragana. Katakana is used for foreign words, which covers a surprising amount of everyday Japanese. Until you can read both, you are learning from romanised text, and romanisation teaches pronunciation habits you later have to undo.

A simple way to learn them

Learn hiragana first, five characters a day, in the order of the chart. Write each one by hand while saying it out loud. Review the earlier ones every day before adding new ones. When hiragana is done, do the same for katakana, which goes faster because the sounds are the same.

Most learners who practise a little every day can read both within a few weeks. After that, everything else in Japanese gets easier to study, because you are reading it the way it is written.