Children's desk chair GUNRIK IKEA
https://www.ikea.com/us/en/p/gunrik-childs-desk-chair-turquoise-00563716/ 

Your child can use this robust chair for many years since the seat depth and the height of the seat and back can be adjusted. The thick padding also makes all the hours of homework and gaming extra comfy.
article number
005.637.16

Depth: 24 3/4"
Height: 40 1/8"
Width: 22 7/8"
Min. seat height: 11 3/8"
Max. seat height: 18 1/2"