Embed doc template in forms

Hi,
I am looking for a way to embed a document template in a form.

The use case is:
Form is used for submission of work requests forcing mandatory fields.
Based on specific selections made by the user in the form, I would like to have the capability of opening a doc template (basically a questionnaire) for the user to fill in.

That way, I will keep the form to its minimal necessary fields and open the questionnaire only when are in need.

Regards,
Baruch