Explanation
On autonomous there's no patching needed. But on the regular DB Cloud services you need to patch the DB and the OS. During the creation on the OCDB the first DB is created automatically Oracle automatically takes care of Operating system Installation/Configuration, Grid Infrastructure, ASM diskgroup Creation/Configuration , and database softwareInstallation and first database on the DB System.
that's all when Creating DB Systems. and then the customer responsible to apply the patches to the database and OS

Explanation
In ATP Service Console,
In the activity screen allows you to perform some basic monitor database activity and SQL queries

In the administration screen allows you toperform some basic administration of the service, like reset the admin password and set resource management rules

Explanation
You can scale up/down your Autonomous Database to scale both in terms of compute (CPU) and storage only whenneeded, allows people to pay per use.
Oracle allows you to scale compute and storage independently, no need to do it together. these scaling activities fully online (no downtime required) in Details page Autonomous Database in OCI console, click Scale Up/Down. Click on arrow to select a value for CPU Core Count or Storage (TB).
Or Select auto scaling to allow the system to automatically use up to three times more CPU and IO resources to meet workload demand, compared to the database operating with auto scaling disabled.