You can add these details in their Employment tab:
Click Access Button
then click Employee.
Select the relevant employee then click Employment tab.
Click Add New for Right to Work and Background Check.
Add the relevant details and click Save.
Other than this, you can upload their background data through data loaders.
If you want to store data within the system or if you wish them to complete these details you can use logbooks and they can complete them as a form.