it is said that time stops at "C". "C"is the speed of light and yet light has a calculated speed. if time stops shouldn't it have infinite speed? it is said that the closer to the speed of light you go the more mass you have. also that when you reach the speed of light you have infinite mass, and yet i have seen calculations for the exact amount of joules needed to make a ship go at the speed of light even though the ship would have infinite mass. does that also mean that there is infinite mass in the universe if there is light? if we go faster the "C" the speed at which time stops will we go back in time?

please help make sense of this someone!!