Most databases contain the same types of pages created over and over again. Think of notes from a weekly staff meeting, bug reports, or design specs. To make this easy, Notion’s database template tool lets you define and replicate certain page structures with one click.
https://www.youtube.com/watch?v=gMFaeZGGxsk
There are two ways to create a template inside a database:
New button at the top right of any database. Choose + New Template.
+ New Template.Note: For in-line databases, hover over the top of them to see the New button. You can also click ••• and choose Templates to create or access existing templates.

On this page, you can define properties and page structure for your template.
Bug in the tags property and Simon Last in the assigned property.Bug Report.This template can be instantly generated every time there's a bug. The new page will automatically put Bug in tags and Simon Last in assigned, and include your chosen headings in the body of the page, like this: