To edit a saved workspace:
Open the workspace: Navigate to 'Workspaces' in the Control Center and click on the desired workspace.
Make changes: Reorder or remove existing layers/tools using the 'Reorder layers' button at the top right corner. Add new layers/tools from the 'All layers' section at the top of the Control Centre.
Save changes: Click 'Save workspace' at the top left corner, select 'Update current workspace' and click 'Save'.