Is it that a iphone 4s cost 50 dollars?

Ok so dis iphone 4s cost 50 dollars at t mobile with inlimit everythin for 40 dollars a month is dat true and ho much for a new line dis is gonna be my first phone

It's a contract. You pay $40 a month for the handset for 2 years. Check whether or not you have to pay extra for a service ie to make calls etc. The "plan" they offer with give you details of what you get for your $40 a month. It may be you will pay extra for any calls or SmS you make. You need to buy insurance too, in case the phone gets lost or stolen or broken because your contract sees you paying $40 a month for 2 years regardless of whether or not you still have them phone or it still works. Read all the words on the agreement so you know exactly what you are agreeing to BEFORE you sign!