How many feet will 8 cubic feet cover?

Answer 1

8 cubic feet is a volume.

feet is a length.

You can not equate a length and a volume.

Thus, if you had 8 cubic feet of cement and wanted to lay an area with it, you would have to ask what the area would be (ie how many square feet) if the covering was say 4 inches thick over the area. Multiplying the area by the thickness gives the volume and we could then answer your question - as it stands we can't.