Less than a week ago Xiaomi promised to release Android 11 Beta 1 for the Mi 10 and Mi 10 Pro and today the company made good on that promise. The Poco F2 Pro is supposed to get it as well, but that particular firmware has not been published yet.
So, if you have a Xiaomi Mi 10 5G or a Mi 10 Pro 5G and are willing to take the risk of running beta software, you can grab what you need from the Mi Forums. You can find the Mi 10 thread here and the Mi 10 Pro thread here.
To install Android 11 Beta 1 on your phone, you must first install the USB Driver on your computer, unlock the phone’s bootloader and flash the ROM with the Mi Flash Tool. More details are available in the forums.
Note that XDA-Developers has alternative download links for the ROM files along with detailed instructions on how to flash them. The process will wipe your phone, so make sure you have a backup before you start.