Hi partner,
The PDF generation capability allows your users to generate PDF files directly from sales records. The capability to create PDF files is supported on the following entities: Accounts, Contacts, Leads, Opportunities, Quotes, Orders, and Invoices.
Please refer to https://docs.microsoft.com/en-us/dynamics365/sales-enterprise/enable-pdf-generation-quote
https://docs.microsoft.com/en-us/dynamics365/sales-enterprise/create-quote-pdf
Here are steps.
1. At the bottom of the site map, select Change area Icon to change the work area and then select App Settings.
2. In the site map, select Overview. under Productivity tools, select Manage of Convert to PDF.

3. set the entity toggle to Enabled and click Save button.

4.Test.
Take the Opportunity entity for example.
(1) Make sure word Templates is updated.

(2) Navigate to an Opportunity record and open it. You will see 2 new menu buttons on the command bar called "Create PDF" and "Email as PDF".

(3) click Opportunity Summary, you will get a PDF file.
The source of the PDF template is the Word template, so you only need to upload your Word template, and then this Word template will become a PDF template.