Starting with Oracle Database 12c Release 1 (12.1), Oracle Database supports the use of Oracle Home User, specified at the time of Oracle Database installation. Oracle Home User is used to run the Windows services for the Oracle home.
Oracle Home User can be a Windows Built-in Account or Virtual Account or a standard Windows User Account (not an Administrator account). Oracle Home User cannot be changed post installation.
If a Windows Built-in Account is used, then no user name or password is required during installation and administration. However, if a Windows User Account is used as Oracle Home User, then you must provide the user name and password during installation and some of the administration tasks.
Virtual Accounts allow you to install an Oracle Database and, create and manage Database services without passwords. A Virtual Account can be used as the Oracle Home User for Oracle Database Single Instance installations and does not require a user name or password during installation and administration.
Oracle Home User is different from Oracle Installation User. Oracle Installation User is the user who requires administrative privileges to install Oracle products. Oracle Home User is used to run the Windows services. You must not log into the Oracle Home User to perform administrative tasks.
Note that the Windows administrator privilege is still required to perform Oracle administrative functions such as installation, upgrade, patching, and other functions.
A Windows User Account used as Oracle Home User cannot have the administrator privileges as it causes the Oracle Universal Installer to display an error message.
Microsoft documentation for more information on different types of Windows user accounts