Does umbilical hernia repair require hospitalisation?

No. Usually an outpatient surgery at a hospital or surgery center. Can go home after recovered from the anesthetic. Unless the surgery is being performed for some uncommon emergency.
Not usually. For smaller umbilical hernias, you can usually go home the same day. For larger hernias, especially if the surgeon makes a larger incision, then you may stay in the hospital to get IV pain medications. But most people go home the same day.
If healthy, No. Generally, if you are in good health, the laparoscopic umbilical hernia repair can be done as a same day procedure. Good luck.