Agreements can be assigned automatically using Partner Types and Regions or manually from the Partner's Details page. 

Automatic Assignment:

When you create or edit an Agreement template, select the "Specific Partner Types and Regions" option to specify the Partner Types and Regions that will be required to sign the Agreement by default.

Manual Assignment:

Go to Partners > click on the name of the Partner to view more details, then click Agreements in the left side panel under the Partner's logo. 

 Partner's Details Page 

Click the "Add Required Agreements" button to select the appropriate Agreement template. 

Partner Agreements Page

Partner Agreements - Add Required Agreement Window

Overriding Required Agreements:

You can unassign required Agreements by clicking the checkbox next to the Agreement in the Pending Agreements section > Remove. 

Partner Agreements Page