How does Bing Xin of the world add blood to others to consolidate the foundation? Silly question ~ but I just practiced ~ I don't want to make jokes in the game

First, select the person you want to add blood to, and then click the skill of adding blood to rejuvenate, and you can add blood. The same is true of Guben. Choose the right person first, and then point out the skills of consolidating the foundation and cultivating the yuan. First, can you add blood to yourself? What can be added to yourself can also be added to others, just for others. . . . . .