Assign a business unit a different parent business
Getting to app feature settings can vary based on the type of app (Unified Interface or the legacy web client) you're using. You might need to adjust the procedural steps in this topic to reflect your app type. See Settings.
Also, we are moving some settings from model-driven apps in Dynamics 365, such as Dynamics 365 Sales and Customer Service, and the Dynamics 365 Admin center to the Power Platform Admin center. See Environment settings are moving.
You can assign a different parent business to a business unit to accommodate changes in your business requirements. When you reassign a business unit, any child business units are also reassigned with it.
Go to Settings > Security.
Choose Business Units.
Choose to select the business unit you want to change the settings for.
On the Actions toolbar, choose More Actions > Change Parent Business.
In the Change Parent Business dialog box, in the New parent business text box, type part or all of the name of the parent business you want to assign the business unit to, and then choose the Click to select a value for New parent business icon .
Select the record for the parent business you want to assign the business unit to, and then click OK.