Using a Word document as an Inventory Template

Using a Word document as an Inventory Template

I want to create a custom proposal (quote) template, based on a template a client has already been using. The existing template is a multi-page Word doc. Due to the character restriction in the Zoho CRM template feature, I have been unable to simply paste in HTML. What is the best way to implement this proposal document as a template?

Based on the client's requirements, there will need to be some form fields to input certain bits of data, then there are other spaces within the document that will auto-populate based on input data mentioned.

Thanks for your help!