In 'Doctor Who', the planet where the Time Lords originated is Gallifrey.
Gallifrey is the Doctor's home world and the planet associated with the Time Lord civilization. It lies in the fictional constellation of Kasterborous and is depicted as a yellow-orange world with a harsh landscape beyond its great cities. The Capitol, also called the Citadel, is the centre of Time Lord political and academic life.
The Time Lords are not simply ordinary residents of Gallifrey. The planet is also home to other Gallifreyans, including the so-called Outsiders, while the Time Lords form an elite society built around advanced science, time travel, and regeneration. The Doctor was born or raised within this civilization, but eventually became a renegade after stealing a TARDIS and leaving Gallifrey to explore the universe.
The planet's name was first revealed on television in 'The Time Warrior' in 1973. Gallifrey later became central to the Time War with the Daleks, and its apparent destruction and eventual rescue became major storylines in the modern series. Skaro is the Daleks' home world, not the Time Lords' origin.