XGameDev game development project brief
https://xgamedev.com/blog/how-to-brief-a-game-development-project/

Write "not decided" wherever you need advice. A short outline is enough.

1. Organisation and contact
Who is requesting the project? Who will make project decisions?

2. Purpose and audience
Who will use it? What should they do, learn or experience?
Where will they use it, and how long is a typical session?

3. First playable version
What is the main interaction? What must the first build demonstrate?
Which features can wait?

4. Entry route and platforms
Website, QR code, LMS, app store, event device or existing application?
Required devices, browsers, connectivity and accessibility requirements:

5. Content and assets
Available design, source code, artwork, models, audio, questions and translations:
Who supplies and approves content? What still needs creation or permission?

6. Integrations and data
LMS, APIs, accounts, multiplayer, leaderboards or analytics:
Required reporting, completion/scoring rules and test environments:

7. Budget, dates and reviews
Budget range or decision the estimate needs to support:
Fixed launch date, review milestones and client dependencies:

8. Acceptance and handover
What checks demonstrate a successful milestone?
Required source access, build instructions, licences and account ownership:
Hosting, maintenance and support requirements:

9. References and unknowns
Examples you like, what you like about them, and questions to resolve first:

Discuss your brief: https://xgamedev.com/contact-us/