The term Ambidextrous, means that a person can use both of their hands equally, for example they can write with both of their hands, or eat with both of their hands. Therefore, in the text given above when it reads "Carlos was ambidextrous, so, when he sprained his right wrist, he was still able to throw accurately with this left hand." This is explaining to the reader that he is able to use both of his hands equally well, and therefore explaining to us what ambidextrous means.
That's correct! The text is using Carlos as an example to illustrate what it means to be ambidextrous. It tells us that even though Carlos injured his dominant hand, he was still able to perform a specific task (throwing) with his non-dominant hand accurately. This showcases his ability to use both hands equally well, which is what being ambidextrous means.
