To create a space/group you should have access to this via your "create" menu. For example, here on the Jive Community:
However this ability is dependent on your permissions for the instance. If you are an admin user in your instance I would suggest reviewing through the following sections of the Jive Documentation for more information on permissions.
Additionally, if you are not an admin in your instance I would recommend reaching out to your Community Manager who should be able to verify if you should have access to create spaces/groups and provision you with access if needed.