As has been said... you need solids to 'subtract'.

However, the fix in this case is easier still...

Select the top and edit it.
Select the top face and use Context-menu > Intersect > with Model.
The sink now cuts a 'ring' in the top.
Select the top's face inside the sink and <delete>

Done. πŸ˜„

The sink now has a matching hole in the top...