How to work with multiple branches?

Question

git

tell me plz
I clone a repository from github with one branch. I create another branch in the clone, and in this branch a file. I'm trying to push to the server, but he swears. When working with a single branch, everything works fine.

$ git push
Counting objects: 5, done.
Delta compression using up to 2 threads.
Compressing objects: 100% (3/3), done.
Writing objects: 100% (5/5), 417 bytes | 0 bytes/s, done.
Total 5 (delta 0), reused 0 (delta 0)
remote: error: refusing to update checked out branch: refs/heads/master
remote: error: By default, updating the current branch in a non-bare repository
remote: error: is denied, because it will make the index and work tree inconsistent
remote: error: with what you pushed, and will require 'git reset --hard' to match
remote: error: the work tree to HEAD.
remote: error:
remote: error: You can set 'receive.denyCurrentBranch' configuration variable to
remote: error: 'ignore' or 'warn' in the remote repository to allow pushing into
remote: error: its current branch; however, this is not recommended unless you
remote: error: arranged to update its work tree to match what you pushed in some
remote: error: other way.
remote: error:
remote: error: To squelch this message and still keep the default behaviour, set
remote: error: 'receive.denyCurrentBranch' configuration variable to 'refuse'.
To D:/git_tutorial/8
! [remote rejected] master -> master (branch is currently checked out)
error: failed to push some refs to 'D:/git_tutorial/8'