Japanese people doesn't have A-Z instead they use hiragana or Katakana letter Hiragana あいうえお A I U E O かきくけこ KA KI KU KE KO さしすせそ SA SHI SU(SI) SE SO たちつてと...
you have to use kana alphabet. it's made up of vowels and sounds, no single consanenta except "n." +aieuo K/g|ka, ki, ku, ke, ko S/z|sa, shi, su, se, so T/d|ta, chi, tsu, te, to N|na, ni, nu, ne, no...