I realized that we're all going to go through pain. It's what you choose to do with it that makes you the person you are." What do these sentences show about Antonio?

Antonio has used the verb "to realize" in past tense which means he has personally experience pain.  And from pain, he discovered that he we cannot always control what happens to us.  We can just control how we react to it.

1.creeping like a snail is a simile used in this poem and it means the child is going to school unwillingly./a child is unwilling to go to school.

2. man becomes very frail and loses his physical strength when he becomes old, so much that his leggings that used to fit him snugly when he was in his youth are now too loose for him to wear, and that his shank has shrunk so much that this worldly stage is too big for a feeble actor like him. although, 'his youthful hose' just refers to his leggings/pants/ to shrink from danger; to shrink from contact.

3.the words "sans" means "without." it is a french word that is often used in english even today. so he is saying that in the last age of a man, the man is without eyes, taste, or anything else. he also says that this is the "last stage of all" and that it is the stage that ends a man's "history."

hope this !

a. the man as a ruler