Hi,

Customization across all the version is same. If will be better if you could have added more details in the question like, what you need to customize, is it the invoice form or printed reports etc.

* To customize reports:

If you are using enterprise, you can use the studio app to customize the report from the user interface itself. See the official documentation here:  https://www.odoo.com/documentation/16.0/applications/productivity/studio/pdf_reports.html

If you are using community and if you need to do it from user interface, if you some technical background, you can achieve by changing the report template by creating an inherited view.

See this example: Customize PDF Reports From User Interface In Odoo

In both version, you can customize by a custom module also.

* To customize user interface:
This can be achieved using studio or from ui tool and using custom module.

If this is not what you looks for, provide more information

Thanks