My bicycle has a label saying size 19" . What is the tire size for my bicycle and the what is the inner tube size?
According to the Bicycle Blue Book, this thing shipped with 700c wheels and 700x38 tires.
So, you need 700x38 tires (or something similar, e.g. 700x35) and a tube which is rated for 700x38 tires (these are sold by ranges, e.g. 700x38-45 tubes).