You can use this modules for debranding https://apps.odoo.com/apps/modules/16.0/odoo-debrand-11/

https://apps.odoo.com/apps/modules/17.0/odoo-debrand-11/

"Discover the debranding module compatible with both the community and enterprise versions of Odoo! Whether you're using the community or enterprise edition, this module is available for all versions."

Hi,
Refer these app:Debranding in mail:https://odoo-community.org/shop/mail-debrand-1532#attr=23696

Debranding in website:https://apps.odoo.com/apps/modules/16.0/website_odoo_debranding/

Hope this helps

What exactly do you want to debrand? Frontend, Backend, mailing, etc... all of them?

The OCA provides some modules for debranding your db.