Keycloak Upgrade from 15.0.2 to 20.0.2 with old realms and users

I have keycloak setup in my Kubernetes environment. It uses image version 15.0.2 and the DB is mssql 15.
I want to upgrade the image to 20.0.2. I need to shift the old realms and users within DB to the new schema as well. Please guide in this regard as could not find clear documentation for the steps to update the DB.

Hi Zunera,
I have the same use case to run. Did you successfully migrate to KC 20.X? If so, pls share your high level DOs and DONTs.

Thanks in advance!