Only Managers & Site Owners can remove users from a workspace.

1.  Open the Workspace.
2.  Click on "manage workspace" and select members.
3.  Find the user(s) that you want to delete.
4.  Tick the checkbox(s) next to their name(s).
5.  Confirm by clicking remove.

This will only remove them from that workspace and stop them from accessing it but will keep all the work they have added to the workspace.
Deleting a user will also free up the User Licence that was allocated, so a new person can be invited in their place.
However, if that user is also a member of another workspace then this will not fully delete their account nor free up a user license.

If you want to restore the workspace for a user who was removed at a later point, just invite them back to the appropriate workspace.
The invite email will contain a link that will take them back to their old workspace, allowing them to join it.
Their access will be restored, but their previous permissions will not - you'll need to amend those settings.

Alternatively, if you require deleting a lot of users from your workspace/site who no longer require any access.
Our support team can assist by performing a bulk delete of your users from the entire site using our admin tool.
If you wish to use this facility then please raise a new support ticket with the following information, refer to this article below.
https://help.kahootz.com/kb/articles/how-to-contact-support-view-your-tickets

* Your Kahootz site name and website URL address of where those users reside.
* A full list of the user's including their email address & UID that you would like removed/deleted.

Note: the bulk delete request can only be raised and approved by the site owners.