There are a few ways to create a new workspace.
Option 1: Select a calendar event from the calendar sidebar to create a workspace
When the workspace is created using this option, all the users in the original calendar event will be invited and added to the workspace automatically.
If you are looking to not send any invitations clear the checkmark or click on "Edit" to select the members of your choice to receive the invitation.
Option 2: Click "Create Workspace" from the workspace sidebar and then select the meeting type (Team Meeting / One-on-One)