Mount Everest is not located in the United States. It is in the Himalayas, on the border between Nepal (Khumbu region) and China (Tibet Autonomous Region).
Its summit is 8,848.86 m (29,031.7 ft)—the highest point on Earth.
The highest mountain in the United States is Denali (Mount McKinley) in Alaska at 6,190 m (20,310 ft). The highest in the contiguous US is Mount Whitney (California) at 4,421 m (14,505 ft).
If you're looking for a major peak in the US, consider Denali, Rainier, Whitney, Shasta, or Elbert—not Everest.