Your iPad10 does not support Stage Manager - this being the iPadOS feature that provides a scaled extended desktop view for an external monitor. While you can still connect an external monitor to your iPad, you will only see a mirrored view of your iPad screen - which will not match the aspect-ratio of an external monitor.
How you connect the iPad to the monitor will be determined by the available video inputs of the monitor. If the monitor supports a direct connection using DP Alt Mode over USB-C, the monitor should charge the iPad over the USB-C connection while the iPad remains connected. Monitors that feature USB-C video input are often considerably more expensive than those that just only feature HDMI or VGA.
Otherwise, if the monitor only supports HDMI/VGA, you will require an appropriate USB-C Adapter for your iPad. By example:
- Apple USB-C Digital AV Multiport Adapter (HDMI):
https://store.apple.com/xc/product/MUF82ZM/A
- Apple USB-C VGA Multiport Adapter
https://store.apple.com/uk/xc/product/MJ1L2ZM/A
Both of these Adapters have both the anticipated video port, plus a USB Type-A port and USB-C pass-through charging port to which you can connect your iPad's Power Adapter.
While undocumented, testing has demonstrated that 4:3 monitors with a display resolution of 1280x1024 and below are currently only usable with iPad screen mirroring; as such, this may limit flexibility.
When choosing a monitor, you might be best advised to ensure that the native display resolution supports full HD (1920x1080) or greater. While the mirrored display will not fill the screen, when using the external monitor to display video content, the full screen resolution will be used.
Also be aware that HDMI connections have a further consideration - namely support for HDCP (High Bandwidth Digital Content Protection). While HDCP support is not mandatory, this becomes important when attempting to stream or view copyright protected video material on an external display. HDCP protected content requires that all devices in the connection chain (i.e., the iPad, HDMI Adapter and Display) all support HDCP. If any component does not support HDCP, you'll not be able to view the protected content on the external display.
Apple's own HDMI Adapters do support HDCP - where many third-party HDMI Adapters do not support HDCP.