The transport of an independent molecule is called uniport. When two molecules move in the opposite direction is called antiport and when two molecules move across the membrane simultaneously in the same direction is called symport.

What is the simultaneous transport of two different molecules in the same direction?

Symport: simultaneous movement of two different molecules in the same direction.

What type of carrier protein transports one molecule in as it transports one molecule out simultaneously?

If the carrier protein carries two molecules in the same direction, it is called a symporter. If the carrier protein moves two molecules in opposite directions, it is called an antiporter. Nevertheless, some porters transport a single molecule from one side of the membrane to the other. They are called uniporters.