If your Site uses Pull Requests as the publishing method, you can configure a Pull Request template to define the default values for the title and body of your Pull Requests.
When you create a Pull Request, you can select which Pull Request template you want to use with the dropdown menu on the Publishing page.
By defining a Pull Request template, you can define the default values for title and body fields, make fields required, control which rich text formatting options are allowed in your Pull Request, and reference a Markdown file for more complex Pull Request content.