how to add tag in github code example

Example 1: git add tag

git tag -a v1.2 
git push origin v1.2

Example 2: git tag a previous commit

git tag -a v1.2 9fceb02 -m "Message here"

Example 3: git tag from commit

$ git tag <tag_name> HEAD   (for the last commit)

Example 4: git create tag and push

git tag <tagname>