You might be better off learning how to play chess, rather than memorizing move lists.
Applying Openings Against Less Experienced players

If you know an opening but not what to do if your opponent plays bad moves, then you need to learn why those moves are bad or else those moves are good.
I already knew those things, I guess I was just asking out of clarification. Thanks. This was in reference to my first comment.
I would consider myself more on the beginner side of chess. I am currently studying Chess Strategy in Action. I know this is slightly old, but would this be a good book for a 400 rated player. The answer is probably yes.
I have watched many videos on openings. They feel very theoretical. As in I feel like they usually discuss the main line. how would you apply this when facing a more beginner player where they don't know any of the lines in a position.