Step 1: Prepare your template
The initial step is to ensure that you have your template prepared. This template will serve as the basis for implementing the Viewer password protected feature.
Step 2: Navigate to Advance Features
Once you have finished creating your template, you can easily activate the Viewer password protection feature.
Find the collapsible section titled "Advanced Features" in the template section, and click to expand it.
Step 3: Set up "Password Protected Field"
To set a password for a specific field, choose any text field in the primary object. You can create a text formula field to automatically update the password for each record.
Step 4: Enable "Is Password Protected"
Now you need to enable "Password Protected Field" , to make the feature work.
Step 5: Update the template
To save your changes, all you have to do is click on the "Update" button. Once you do that, the document will be generated in the right-hand preview with password protection enabled.