Welcome aboard!
I made the jump over from ST several years ago, and no regrets.
The transition is all manual, and I won't lie -- it'll be a bit of a slog... I suggest documenting your current ST setup with screenshots, notes, etc (in whatever detail is most helpful), so that you have some reference points as you're recreating things in Hubitat.
One nice thing about Hubitat is the (optional) reasonably-priced Hubitat Protect subscription -- it enables extended hub warranty and full backup restore if something goes sideways down the road.
This thread will hopefully be helpful with the move too:
