Create workspace

Hi,

The question may sound very stupid but how do I creat a workspace?

The FAQ indicates to "Click 'New' button from the top left side panel and select 'Workspace' option from the drop-down menu"... but there is no "New" button.
And contrary to the pic that comes with the FAQ, I've no "Workspace" field listed below the "Share with Me" field in the left panel.

I'm on the free plan, is it a limitation of this plan, not to be able to create any workspace?
If yes, how can I share a folder structure ?

Thanks.