To change your HOME variable (containing the path to your home directory), you can try different approaches.
The linux "inhouse" solution would be to edit your ~ / .bashrc file (or create one) to say something like
export HOME="/d/user"
Next time you run GitBash and type
cd ~/.ssh
it will go into /d/user/.ssh if the directory exists.
Now according to danlimerick and GregK you can also set the HOME variable directly on Windows. The links also mention how you can change the startup folder by changing the properties of the shortcut.
Similar questions with answers can be found here and here .
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