Hello Ahmed Mohamady, 

    To Hide the section that you have mentioned, Please follow below steps : 

    1) Create a Module, after that create a folder structure as shown in below image.

    2) Register the pos assets in __manifest__.py file.

    3) Add below code in .xml file.

 ///// code in comment

    4) Here is the screenshot of expected Output :    

I Hope this information proves helpful to you.

Thanks & Regards,

Email:   odoo@aktivsoftware.com           

Skype: kalpeshmaheshwari