Yes, it is either
12-2 Romex or 10-2 Romex...."cleeds" is on it!
You can debate which one to run for a 20 amp duplex outlet but what you have is a Black Positive conductor, a White Neutral conductor, and a Green Ground conductor.
In the Service Panel: the 20 amp breaker will have only the Black wire,
The White will be attached to the Neutral Bar and the Ground to the
Ground Bar.