Is the Grand Canyon in Yellowstone?

No. The Grand Canyon is located in northern Arizona, carved by the Colorado River. Yellowstone National Park is primarily in Wyoming (with slivers in Montana and Idaho), centered on the Yellowstone Caldera. They are ~500 miles (800 km) apart by road. Each is a distinct geological wonder: the Grand Canyon exposes 2 billion years of strata; Yellowstone showcases the world's largest concentration of geothermal features.