Modeling Character, not sure how to go about eyes

Im trying to model this character [ Archibald ] In blender
But im having some trouble

as you can see i got the body and arms down perfectly but im having trouble getting the mouth and eyes done,
What would be a good technique for the eyes here, as you can see they are square with lined pupils.

I’ve seen people do eyes by making a new object and shaping it to match the shape, should i do that? make an a square eye and then inset and extrude for the pupil? Ive done some basic tutorials on udemy but im still pretty new to this

can someone help me