To create remote Git branch in IntelliJ idea one should:
- Commit and push all your changes first
- Create local branch by going to VCS -> Git -> Branches -> New Branch. You can see your local and remote branches in this menu too, as well as current active branch.
- After you created local branch to make it remote you need to do VCS -> Git -> Push, set bottom checkbox "Push current branch to alternative branch", specify your new branch (should be already there) and click "Push".