Answer:
The mirror is opaque while the lens is transparent
Step-by-step explanation:
The lens is transparent throughout (lets light pass through), while the mirror reflects light. You are basically asking for the difference between a lens and a mirror
But how about the the behaviors of the convex mirror and convex lens? The convex lens will let light pass through and focus it on the other side of it. If you stand on one side of the lens, you can see what is on the other side of it. Think about a camera lens that's just curved!The convex mirror will reflect the light on the same side of it you'll basically will just see yourself but you'll look funny.