"""Usage limits
GitHub Pages sites are subject to the following usage limits:
* GitHub Pages source repositories have a recommended limit of 1 GB. For more information, see "About large files on GitHub"
* Published GitHub Pages sites may be no larger than 1 GB.
* GitHub Pages deployments will timeout if they take longer than 10 minutes.
* GitHub Pages sites have a soft bandwidth limit of 100 GB per month.
* GitHub Pages sites have a soft limit of 10 builds per hour. This limit does not apply if you build and publish your site with a custom GitHub Actions workflow
In order to provide consistent quality of service for all GitHub Pages sites, rate limits may apply. These rate limits are not intended to interfere with legitimate uses of GitHub Pages. If your request triggers rate limiting, you will receive an appropriate response with an HTTP status code of 429, along with an informative HTML body.
If your site exceeds these usage quotas, we may not be able to serve your site, or you may receive a polite email from GitHub Support suggesting strategies for reducing your site's impact on our servers, including putting a third-party content distribution network (CDN) in front of your site, making use of other GitHub features such as releases, or moving to a different hosting service that might better fit your needs."""
- https://docs.github.com/en/pages/getting-started-with-github...
I managed to use 25 GB in a month for games that were less than 5 MB(!) each (shareware model, so more downloads than sales), and that was for something generating mere hobby-level income, not full time job replacement income.