The standard inventory doesn't use 'slots', so the display also doesn't have that option.
However, there's an optional slot-based inventory system available for that, the
inventory containers. You can basically manage which kind of content (e.g. items, equipment or based on item types, etc.) is stored in an inventory container and also have multiple containers.
Displaying this inventory (with empty slots) is done via an
inventory container (slots) menu part.
There's currently no tutorial available, but it's planned to be available soon(ish) - getting Covid somewhat derailed my schedule, though :)