GitBash is one of the options one has to operate a Bash environment directly inside Windows. However, there now is the option to use the Windows Linux Subsystem (WLS), that can be launched from the classical terminal (cmd) by entering the command bash. However, despite both WLS and GitBash existing on the same Windows instance and environment, I don't yet see a direct way of launching the more powerful WLS environment from a GitBash shell.
Definitely, there would be the option of launching cmd inside GitBash, and then attempting to launch WLS by entering bash next, however, testing on Windows 10, I find that doing this has that bash command launch a new GitBash shell from the classical terminal shell instead. How to launch WLS instead?
NOTE: "Windows Linux Subsystem" == "Windows Subsystem for Linux" in this case. I just prefer to use the former.

wslcommand now used to runwsl.exe, which you may wish to try.wsl -e "cal"works, however runningwslon its own doesn't -- seems to just hang -- that is when invoking WSL from GitBash. If on classic CMD instead, all works fine. Thanks!