Yes, you can either add an additional document during the envelope creation or if you need a Recipient to add a document you can add an "Attachment" tag assigned to that Recipient. During envelope creation you just upload another document. If using the "attachment" tag you add it to a location and either set that attachment tag as Required or Optional.

Here is a DocuSign article on adding an attachment tag

https://support.docusign.com/en/guides/signer-guide-signing-adding-attachments-new

requirement is to attach the policy pdf as attachment and send to customer along with pdf that needs sign. Is this possible? I dont want customer to give option to attach something. Read properly