Four Paws Wee-Wee Puppy Training Insta-Rise Border Pee 50-Count 22" X 23" Standard Size

How do you know which white (front/back) pad is the correct one for the dog to pee on?

Do these Insta-Rise padscome in a size larger than 24" x 24"?

Why does my male 5# small dog go to the very edge to pee, and urine goes under the mat and on the floor even when its a brand new pad?