By default, Git does not autocomplete commands and branch names. If you have installed Git on Windows, autocomplete is available if you run the "Git Bash" program. For OS X and Linux, you can install the auto-complete tools and set up your environment to load them automatically. See this page for instructions: https://git-scm.com/book/en/v2/Appendix-A:-Git-in-Other-Environments-Git-in-Bash