Using the :Git command, you can run any arbitrary git command from inside Vim. I prefer to switch to the shell for anything that generates a log of output, such as git log for example. But commands that generate little or no output are fair game for running from inside Vim (:Git checkout -b experimental for example).
At Vim’s command line, the % symbol has a special meaning: it expands to the full path of the current file. You can use this to run any git command that expects a filepath as an argument, making the command act on the current file.