Choose the sections you want — summary, change-type checklist, review checklist — and the tool assembles a GitHub pull_request_template.md.
Save it as .github/pull_request_template.md and GitHub will pre-fill it into the description box every time someone opens a new pull request.
Yes, as a starting point — review names, paths, and details against your actual project before committing.
No. Everything is built client-side in your browser; nothing is sent anywhere until you commit it yourself.