If the Soul Knight wanted to place the book in the skill bar, he had to first determine the location of the book. Normally, when a Soul Knight's skill was used, the book would have been occupied. If the book's position was already occupied, then you would need to unlock it first and then move it to the skill bar. Generally speaking, players could unlock items by completing some missions or obtaining some rewards while playing games. If the book's position was not occupied, then he needed to find the Soul Knight's skill block and move it to the right place. Generally speaking, it could be done by opening the skill bar and clicking on the person who wanted to move the item and then selecting the "Move to" option. It was important to ensure accuracy when moving items to the skill bar. If you accidentally move other items or the position of the item is incorrect, it may cause the item to be unable to be used normally.