Regarding adjusting the height of a desk or chair:
Desk: Just turn the white hand crank to adjust the height.
Chair: You only need to manually adjust the height of each level upwards. If you need to lower the height of the chair, you need to adjust the chair legs to the highest position, then gently release them to lower them to the lowest position, and then adjust the height step by step to the appropriate height.

Desk and Chair Tilt Desktop Shelf Assembly InstructionsDesk and Chair Tilt Desktop Shelf Assembly Instructions

Desk Assembly Instructions

Desk Shelf Assembly Instructions

Chair Assembly Instructions

Chair Height Adjustment Instructions

Desk: Just turn the white hand crank to adjust the height.
Chair: You only need to manually adjust the height of each level upwards. If you need to lower the height of the chair, you need to adjust the chair legs to the highest position, then gently release them to lower them to the lowest position, and then adjust the height step by step to the appropriate height.