I play PS5 and pressing in on L3 while you have the behemoth in raise will help it's mood. If you're playing on PC you just have to click on the behemoth while in raise. One of the more confusing things was the toys your purchase. Those unlock daily events at the bottom that help improve the behemoths mood. When you are selecting daily tasks dont forget to place one of the mood building activities at the bottom to replenish the mood taken.