Publishing your addon is incredibly simple. You must use a git-based repository site, like GitHub or GitLab.

Make SURE that you created a .gitignore file before publishing.

Then, using git, initialize a git repo with:

$ git init

Next, connect your remote repository which is on GitHub or GitLab with:

$ git remote add origin REPO_URL_HERE

Then, run these next commands to push your code to the remote repository:

$ git add .
$ git commit -m "initial commit"
$ git push origin main

This will create a new branch on your remote repository called main where your addon will be stored.

Congratulations! You can now add the addon by grabbing the Git repository link and inserting it into the addons option in OpenGameInstaller!