A ukulele capo is a very handy tool especially for newbies. It can come to the rescue when you need to change the key of a piece and don’t have time to learn the song in a new key. And using a capo can help you to understand the relationship between chords and keys.
As you advance you may not need to use a capo as often to play in more difficult keys. Try to learn as many chords as possible, so you can play in lots of different keys. You’ll be a better ukulele player as a result.