How far did they bury Mummies and did they really stick a hook up the mummy's nose and pull their brains out with the hook?

Answer 1

Assuming the question is about Egyptian mummies, the depth the mummy was buried depended on the family's wealth and social status.

Only the more wealthy people could afford the full mummification process. Poorer people were buried in shallow desert graves, where dryness of the desert would create a natural mummy. The wealthier mummies would be interred in tombs, the most commonly recognised tomb is the mastaba, the body buried deep (~30ft) below the ground, the shaft blocked up by rocks.

As for the mummification process - yes, the brain was removed. the Egyptians did not know what purpose the brain functioned, they believed that thought and personality lived in the heart. To avoid damaging the head, the brain was pulverised using a hook on a wire, and removed through the nasal cavity.