How to do the task of breaking the arrow and recasting the magic sword of Jiuyin Zhen Jing Donghai in the early stage?

When you first enter Penglai Island in the East China Sea, you will see a man in black, who will take the task there, and then go back, and you will see a big tree that has been cut down. Pick it up and go to the man in black, and then go back and get it about four or five times. Hope to adopt!