How many bases does a quadrangular prism have?
Any such figure has only one base; the one that it stands
upon.
If you are asking "How many faces does the quadrangular prism
have?" then its "ends" are both quadrangular shapes (i.e.
rectangles) and there are 4 more rectangles forming the "length" of
the prism so the answer is 6
These rectangular shapes are more accurately called "faces"; the
edges of the rectangles are called "edges", and the corners are
called "vertices".
Your quadrangular prism has 6 faces, 12 edges and 8
vertices.