The X100 line has a fixed lens, it does not swap out. It’s a bit of a larger, fancier point and shoot that does not zoom. They look really nice and I’ve always wanted one!
I have an X-T2 and have started a collection of lenses. The 56mm F1.2 is a bokeh monster with the autofocus speed of a slug! But when it hits it is beautiful. They just came out with a new version of the 56mm lens that might do better in Auto Focus, and they are up to the X-T4 which has a bunch of features that are nicer too, like IBIS.
Note that the Fuji cameras are unique in that they use a custom colour filter, not a Bayer filter on the sensor. This can affect the RAW processing depending on how you might want to do it. Honestly I got into Fuji cause a friend shot with it, lent me the body when he was out of country for a while, then I just got used to it and that was that. The XT line has more dials than a lot of other makes, some people like that.
I’ve decided on suggesting this to people who ask what camera they should get:
1. Pick your budget first
2. Pick the type (point and shoot, mirrorless interchangeable lens)
3. Go to a camera store and pick up some of the models you might be interested in. See what you like the feel of and the interface of. Between all the big companies, you can’t really go wrong.
4. Don’t go all out on the body (go used!) and get nicer lenses. Once you pick a make with a certain mount, you can have the lenses for life and upgrade the body as you go along. Try 2 lenses to start a prime portrait lens and a zoom in the normal to telephoto range to be able to be a bit away from your kids but still get a tight shot.
You can take a look at my Flickr account and see that a lot of the pictures up there are with a Nikon D40 and a $200 prime lens. In good light, it still takes fine pictures! My son and daughter now runs around with it and get some great shots from their POV.