The correct phrase to fill the blank and complete the sentence is sacar la basura.
Para sacar la basura necesito una bolsa de basura.
You should only address others with “tu” when they are your age or younger. You use usted with people older than you like a grandparent or some random older person on the street you might run into.
ES because esta means something like to be and esta is a girl and pablo is not a girl lol and es is to be so pablo is playing with his homie