You can find the workspace settings by clicking on your profile picture in the bottom left corner of the sidebar. The Workspace Settings are only accessible to the Workspace Owner and the Workspace Admins (see permissions).
The "Workspace settings" are divided into three parts; Settings, Authentication and Billing.
In "Settings", you can change the title of the workspace, change the logo and delete the workspace.
In "Authentication", you can enable Google G suite authentication for your workspace members or set up signup access for a specific email domain.
In "Billing", you can subscribe to a plan, change your credit card details and see previous transaction.