Steve MaddenWomen's Insulated Quilted Puffer Parka Winter Coat with Hood (S-XL)

Is this coat windproof? water resistant?

I would like to know do this coat run big my daughter , wear her tops 2x to 3x in tops pants 18 to 20 , 5"4 and weigh about 240 pounds what size

I’m debating between a medium and large. I measure 42 inches in hips. Will a medium zip around my hips without being too snug?

What are size equivalents? What should I order if I am wearing a 18/20 plus size?