I use an iPad as a second display, usually with duet display as I have a Mac notebook (but I think I remember it also works on PC, but it’s not driverless) but there is also a hardware way using hdmi etc called Luna display.
I've tried the Duet display solution and was not super thrilled about it; mostly the issue was the refresh rate. That was with a 9.7 Pro, via the Lightning cable.
Edit: Just tried Duet again. Aside from a bit of mouse lag (and audio-video sync issue if watching a video) it seems better than I remember. Set to 60fps, high power, 1536x1152. The 9.7" Pro only transfers at USB2 speeds as opposed to the newer models and all 12.9" models IIRC (USB3), so that may be a factor.
This HP panel is 1080P 60hz and mousing is fluid and videos are smooth, same as the native display.
Another thing to note: it does have backlight bleed with a black screen, typical for IPS panels.