I have a kallax connected to a desk top, like this. It's a legitimate ikea combo so they do actually sell the fittings to do it. My partner and I both had desks for gaming pcs before anyway - I've now got a gaming laptop instead. Fortunately only one of us works from home, as otherwise we'd have move one of the desks somewhere else.
Chair is from work, I had a chair but going from a couple of hours to a full working day meant I needed a proper computer chair.
I have a work laptop, but bought a stand from amazon.
Technically I have a screen from work, but its not actually used, as I've recently upgraded to a 27inch acer, its technically a gaming screen. So work has provided a reasonable one, just I wanted better and something for personal use.
Mouse and keyboard came through work, and they also provided a dock for the laptop - I think they were planning an upgrade way before covid hit, so everyone was going to a laptop + Dock set up.
Oh and I bought a lamp for early winter mornings. There is also a Google home mini tucked on top of my dock and under my screen. Plus a foot rest under my desk.
Work also provided I think a £250 allowance to claim from, but I never did. The only stuff I 'needed' was little things like lamps and footrests, and tbh couldn't be asked with the faff.
I was keen to make it a work space - but also wanted to be able to make a reasonably quick transition to personal one. So in theory all my work notebooks, mouse and keyboard get tucked into the kallax cubby, and the laptop is already propped out the way.