All diptran insects have 2 sets of wings as flies , mosquitoes etc .
An airplane with 2 sets of wings is known as a biplane.
Flies, like all insects, have six legs and two sets of wings.
monoplane
Biplane
A Biplane.
Bi-plane
two sets of wings
Yes there are insects that look like dragonfly but have only one pair of wings namely, mayflies( with one set of triangular wings) , Diptera, and crane flies.
A bi-wing.
A DragonFly
ladybugs have two sets of wings