Choosing a Harmonica
Decide based on the tunes you want to perform

What would be a good choice for you first harmonica? The choice of whether to choose a single- or double-reed harmonica would be best determined by the music you want to play and the notes you want to produce. There are also different types based on key. If you have no particular preference, then it would probably be best to start with a C-tuned instrument. After starting to play, it may make sense to assemble instruments tuned to other keys, depending on the song, such as G-tuned, A-tuned or A-major-tuned.
A chromatic harmonica can also produce sounds in various keys with a single instrument.