VSCode in CloudShell - bobbae/gcp GitHub Wiki
In Cloud shell, download a release of code server which includes vscode:
$ wget https://github.com/cdr/code-server/releases/download/v3.9.0/code-server-3.9.0-linux-amd64.tar.gz
$ tar xf code-server-3.9.0-linux-amd64.tar.gz
$ cd code-server-3.9.0-linux-amd64/
$ ./code-server
Then web preview to connect to vscode.