Xbox: How you look tab is missing from Account - Profile

I need to change the real name that is on my childrens account for xbox. I would like to edit this and cant find the how you look tab when going through their profile or even using mine through family settings. Please help me do this on the console if possible or show me a way on the website. I couldnt find any help for this problem. Thank you!

Edit: I am not looking to change the gamertag but the real name on the microsoft account that the kids use with me

:)