From Setup, click Sandboxes or Data Management | Sandboxes. Click New Sandbox. Enter a name and description for the sandbox. You can only change the name when you create or refresh a sandbox.
See, Sandbox does not comes with any free account as per my knowledge. I have created many free trial account but Sandbox option is not there. Sandbox only comes with Production Account and there is a limit of creating sandboxes after this you need to contact to Salesforce other wise Sandbox option will not be available in Data Management section as you are showing up in production environment.
Click New Sandbox.
Enter a name and description for the sandbox. You can only change the name when you create or refresh a sandbox.
Definitely you will get a option to create full copy sandbox...
And provide course name as "apex" or "Buliding Applications on Force.com"