Hi @spfxuser ,
Could you please share a bit more about your scenario?
Which type Environment do you want to create in your Power Platform Admin Center? Production Environment or Trial Environment?
Currently, if you want to create a Production Environment or Trial Environment in your Power Platform Admin Center, and want the 'Creator' to be the 'SYSTEM' rather than yourself, I afraid that there is no way to achieve your needs in PowerApps currently. When you create a Production Environment or Trial Environment in your Power Apps, the Creator would be the user who create this Environment.
Within Power Apps, only when you create a Community Plan Environment (Developer Type Environment), the Creator of this Environment would be "SYSTEM", do you would like to create a Developer Type Environment?
More details about Community Plan in Power Apps, please check the following article:
https://docs.microsoft.com/en-us/powerapps/maker/dev-community-plan
For your second question, do you want to remove the user who creates the Environment from the admins group? I afraid that there is no way to achieve your needs, you could not remove the owner of the Environment from the Admin Groups.
More details about Environment in Power Apps, please check the following article for more details:
https://docs.microsoft.com/en-us/power-platform/admin/environments-overview
Regards,