A good argument is both
An argument is valid if the conclusion necessarily follows from the truth of the premises.
An example of a valid argument form:
1. If x then y
3. Therefore, y
Validity doesn’t say whether the premises are true. It only says that the structure of the argument is such a way that IF the premises are true, then the conclusion necessarily follows.
An argument is sound if and only if:
A. The premises are true
B. The argument is valid
An example of a sound argument:
1. All men are mortal
2. I am a man
3. Therefore, I am mortal
Soundness does indeed answer the question of whether the premises are in fact true.