Is it the Redmi 7 or 7 Pro.
Are you currently on MIUI 11, or 12 to 12.5.
I think it will get MIUI 12.5 but will stay on Android 10. Security patches should still come, but probably every 2 - 3 months for the previous or current month. (guessing here)
I have 2 Xiaomi devices (a Mi 10 Lite and a Poco F2 Pro) in the UK, both 1 year old.
There is generally a few good web sources for their updates, but MIUI updates can take months to reach every model that's eligible in their (Xiaomi) constantly revised list; plus it can depend on your world region.
I couldn't find enough information on an initial search, the info is usually offered to me by Google, but I'll try again later.