If you don't have an Oracle database to use for testing purposes, I recommend that you consider a pre-built developer virtual machine (VM) that's already installed and configured. Prebuilt developer VMs are available from the Oracle website. Another option is to leverage an Oracle VM template from Microsoft Azure. If you want to perform your own installation, you can download the Oracle database from the Oracle Technology Network website.
For information about using Oracle Data Access Components (ODAC) in a test database, see "Connecting to an Oracle Database from SQL Server and Microsoft BI Tools."