One option is to upgrade DB Runtime 13 which supports Python: 3.10.6 if that suffices.Another is to create a docker image. Refer the below stackoverflow post https://stackoverflow.com/questions/72863008/how-to-upgrade-python-version-in-databricks
From the documentation, update statement is only supported for Delta Lake tables.https://docs.databricks.com/sql/language-manual/delta-update.html. Can you check if your tables are delta