Answer:
It depends on the degree of the fracture.
If it is just a crack/hairline fracture, then the treatment can be easy as buddy-taping it to the finger adjacent to it.
If the fracture is such that the bone is separated into two, you may need to go to the doctor to have it put back into the right position for it to heal. The doctor may give you a finger splint to immobilize the finger.
It takes around 4-8 weeks for it to heal completely.
To check how severe the fracture is, an X-ray is needed.