Minor nit: the kana are not alphabets, they're syllabaries. Each character represents a complete syllable (except ン/ん) as opposed to representing a consonant or vowel sound.

They are really straight-forward to learn as, unlike in English, they don't have di and trigraphs and extremely few pronunciation exceptions. Learning the characters can be done in an afternoon, though of course being able to read them quickly will take quite a bit of practice.