To add an expiry date to a field - select the relevant Section from the Template Editor.
Double click on the field you wish to edit, this will bring up the Field Editor.
Set as an Expiring Check
Under Validation Rules click on "Add a Rule"
Then select "Expiring Check" from the drop down:
Now you can set when this check will expire:
Once you are happy, click "Save Changes".
Click on "Publish Changes" once you have finished using the Template Editor to make the changes live on your system.
How will this be presented on a Profile Page?
Please see the below Help Article: