Yes skill. There are skill based casino games some examples are poker and blackjack which I know of very well. In these games of skill you require the strategic thinking and decision-making skill. You also require card counting skill as well as the skill to outsmart whoever you are playing against.
I thought "casino gambling" refers to slots or in-house games like dice, crash, plinko etc, that's why I ask what skills that you will play in those games, because it's all luck based games which doesn't require any skill.
While poker and blackjack, I would say they're called as table games instead of "casino gambling", obviously the one who familiar and experienced in those games have higher chance to win than the new gambler.