To migrate an on-premises Oracle Database to Oracle Autonomous Database, you can use the following methods: Oracle Zero Downtime Migration, which provides a way to migrate databases with minimal downtime; Data Pump Export/Import, which is a flexible and widely-used method to move data between Oracle databases; and PDB Unplugging/Plugging, which involves unplugging a PDB from its source and plugging it into the target database. These methods are designed to support migrations to Oracle Autonomous Database.