Is working at night forbidden because of Allah Almighty's saying: "And We made the night as a covering and We made the day for livelihood"? And is designing and drawing cartoon characters and animals by embroidery on children's clothes forbidden?

Working at night is not inherently forbidden, unless it leads to neglecting prayers or other obligations. As for the Almighty's saying: (And We made the night a covering, And We made the day for livelihood), it is a declaration of God's signs and not a prohibition of working at night. Drawing inanimate objects like trees and flowers is permissible, but drawing animate beings in their complete form is forbidden. However, it is permissible to draw them if they are incomplete, such as a head without a body, but it is better to avoid it.