I've been using a BT keyboard & mouse (Logitech Keys & MX Master 3) with my iPad since they announced the proper mouse support. Combined with the USB-C to HDMI

I've been using a BT keyboard & mouse (Logitech Keys & MX Master 3) with my iPad since they announced the proper mouse support. Combined with the USB-C to HDMI multi-port adapter (which provides a USB-C pass-through port, USB-A port, and an HDMI port), it's close to using a desktop. I'm used to coding over a terminal, so I use the app Blink Shell to do anything like that since it fully supports external displays (most apps and the iPad interface will display windowboxed). Blink is open-source, and they provide instructions on their github repo, but you can also fund the project by buying it via the App Store.