Mount Everest (8,848.86 m / 29,031.7 ft) straddles the Nepal-China (Tibet) border in the Mahalangur Himal sub-range of the Himalayas. The Himalayas are a distinct mountain system formed by the Indian Plate colliding with the Eurasian Plate (~50 Ma ongoing). They separate the Indian subcontinent from the Tibetan Plateau.
Everest sits on the South Asia / Central Asia boundary. The standard climbing route (South Col) approaches from Nepal (South Asia). The North Ridge route approaches from Tibet (Central Asia). Neither is East Asia.
China's political claim over Tibet + Western media shorthand ("Asia's highest peak") blurs the subregions. The Himalayas are their own orogenic belt—distinct from the Tian Shan, Altai, or Hengduan ranges that define Central/East Asia boundaries.
Lhotse (8,516 m, 4th), Makalu (8,485 m, 5th), Cho Oyu (8,188 m, 6th) — all Mahalangur Himal. Shishapangma (8,027 m, 14th) — entirely in Tibet, Jugal Himal. The 14 eight-thousanders cluster in Himalaya/Karakoram—neither East Asia.