why can´t I access my library of games i just want to make my banned account my home Xbox

https://www.reddit.com/r/xboxinsiders/wiki/ideas

Once you're banned, you forfeit anything you had on the account. If you didn't already have your console set as your Home, there is no way to change that once it's banned.

Fair enough but is there a place we one can recommend features that can be add in a update on Xbox?

https://www.reddit.com/r/xboxinsiders/wiki/ideas

Thank you so much and have a good rest of your day

Yes, it is called game sharing. To do this you need to sign in to your account on their Xbox, go to settings --> personalization --> my home xbox --> Make this Xbox my home Xbox. Now just sign in to your children's account(s), go to library, then full
library, and they'll be able to download the games. Also, if you have a gold membership, they will have access to it too. Hope this helped!