Go to the starting point of the project
git checkout origin master
fetch all objects
git fetch origin
Make the branch from the tag
git branch new_branch tag_name
Checkout the branch
git checkout new_branch
Push the branch up
git push origin new_branch
ex.
git checkout origin master
git fetch origin
git branch release_a_branch release_a_tag
git checkout release_a_branch
git push origin release_a_branch