yes but adjacent angles are not.
two pairs of congruent angles in a rhombus
Yes, it is one of the ways to prove a figure is a rhombus. If adjacent sides are congruent, then the figure is a rhombus.
A rhombus has 4 congruent sides, but it does not necessarily have 4 congruent angles.
If all adjacent angles are congruent, it can only be a rectangle (or square).
A rhombus always have 2 pairs of congruent angles, yes.
A square, but not a rhombus because a rhombus does not have four congruent angles