Hi, KJGJ, and welcome to UU! You'll find a wealth of knowledge here pertaining to all things uke-related. There have been many, many threads about picking a first uke. If you search "first uke" I'm sure you'll get a start.
Much of the decision will be based on your budget. Most folks here recommend buying the best uke you can afford. Most folks here also end up owning many ukes, due to the common malady known as UAS (ukulele aquisition syndrome). Good starter ukes can be had for as little as $30-$40, such as the Makala Dolphin. From there the sky's the limit.
Some of your decision will be based on size. The small, traditional uke is the soprano. Next up in size is the concert, followed by the tenor and then the baritone. As the size increases it approaches that of a guitar, and so does the sound. The baritone sounds much more guitar-like than a soprano. The soprano, concert and tenor share the same tuning (usually), but the tuning of the baritone is different.
A portion of your decision will be based on appearance. This is totally subjective, and only you know what you will like.
I opted to start with a lower mid-range priced uke in concert size. I bought a Kala KA-SC from Musicguymic on eBay. Mike has a stellar reputation here, and is highly recommended as a source for ukes in any price range.
Do some reading about first ukes and pick one you like. Let us know what you decide!