You can chop the rest of the line off with the D key in normal mode. This deletes the rest of the line starting from the character under the cursor.
You can also use the C key to change until the end of the line. This works exactly the same as D, but it drops you into insert mode after making the deletion.
Try it in the editor. On line 5, use the D command to delete the quoted text from the end of the line. Then, on line 10, use the C command to change the name after the colon to your own name.