Check out example codes for "my html doesn't show up github pages". It will help you in understanding the concepts better.
Code Example 1
Cause 1: make sure you have an index.html file Cause 2: make sure that in GitHub Pages (under settings) your source is the master branch For anything else look here: https://stackoverflow.com/questions/45362628/github-pages-site-not-detecting-index-html#:~:text=Go%20to%20settings%20for%20your,the%20gh%2Dpages%20branch'.
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