Mail Merge Fillable Fields updating CRM fields

Mail Merge Fillable Fields updating CRM fields

Hello All,

We use Zoho Sign with mail merge templates to send contracts for signature to our clients.

I would like to know if its possible to have a fillable field (Checkbox) in the document that could update a field in the Contacts module on Zoho CRM when the document is signed and submitted. 

I believe it would be like mapping the 2 fields previously and then, when the signer clicks on the checkbox and submit the document, the field on the CRM is updated.

Thank you for your help,