Answer by Michael Lihs for Create a repo in Gitlab using CLI

gitlab-cli is no longer maintained, the author references the Gitlab module to be used instead - it also includes a CLI tool.

For your specific request - namely creating a project on the command line, use the following command:

gitlab create_project "YOUR_PROJECT_NAME""{namespace_id: 'YOUR_NUMERIC_GROUP_ID'}"

Be sure to use the option namespace_id and not group_id! If you are not sure what your GROUP_ID is, you can use

gitlab groups | grep YOUR_GROUP_NAME

to find out.

The parameters for each command can be inferred from the API documentation. Any non-scalar valued parameter has to be encoded in an inline YAML syntax (as above).