To modify the default path used by Git, you can modify the environment variable GIT_DIR. The GIT_DIR environment variable specifies the path where Git repository metadata should be stored. By default, this is set to .git in the root of the repository.
To modify the default path, you can set the GIT_DIR environment variable to the desired path. For example, to set the default path to ~/myrepo/.git, you can do the following:
export GIT_DIR=~/myrepo/.git
This will set the default path for Git commands to ~/myrepo/.git. Note that this change will only apply to the current shell session, so you may want to add this command to your shell startup script (e.g. .bashrc) so that it is applied every time you open a new terminal.
Keep in mind that changing the GIT_DIR variable may cause some Git commands to work incorrectly or not at all, especially if you are using Git submodules, since their .git directories are relative to the root of the repository.