Firstly, we should know what are tags in Git. Tags in Git are the reference points in the Git history that denotes special events. It is not a rule to tag the releases. You can tag any commit for any purpose you want.
Steps to create a tag in Git:
1) Open Git Bash in the working directory.
2) Check if you have a clean working directory.
3) Execute the following command to view the commits:
git log --oneline
We can now create a tag onto any of these commits. Let's tag the last commit on the dev branch by executing the following command:
git tag ongoing dev
Note: A commit to dev branch will not reflect in any other branch. It is personal to dev command only.
Now you can check yourself by executing git log --oneline command that the tag creation is successful.