Hosting dot-hugo theme in github "plugins folder" not found in gh-pages branch

I have created hugo site with “dot-hugo” theme. For hosting we used github, while doing we created “main branch”. It auto created gh.pages branch, from this branch site is published and some files are missing, we added into main branch and committed again but now it is not reflecting into gh-pages branch.
How can we update the gh.pages branch in github after doing some changes committing main branch?

If you are using this workflow the gh-pages branch is automatically updated.