Ken is great at offering help to get you started. While it is hugely customizable, getting a basic system up and running isn’t too hard. An RPi is your easiest path, but a home Linux or Windows server running Apache also works fine.
Sounds like you had and still have ST? In that case, I’m assuming you’re aware of the krlaframboise “Other Hub” apps/DTHs that allow you to expose most Hubitat devices in ST, which would still allow for (among other uses) monitoring and control via ActionTiles. That’s what I’m doing for the moment since I can’t decide between HADash (I already have Home Assistant, too) or HousePanel or just waiting for Hubitat’s proposed dashboard.