The part of the brain where planning, language, and advanced thought occur is the hypothalamus amygdala hippocampus brain's hemispheres

brain's hemispheres

Explanation:

The brain's hemispheres is known as cerebral hemispheres. They are two in number: The left hemisphere and right hemisphere. These two hemispheres work hand in hand with each other.

The brain' hemispheres are responsible for planning, advanced logic or thinking, control of the human thought process and language.

Any damage or defect to the brain's hemispheres results into a stroke whereby the person looses major control of their motor skills, experience difficulty in speaking, loss of perception e.t.c.