Create your product's field value in CSV format and start the import process available at Product TREE view.

Helpful links:
https://www.odoo.com/forum/help-1/question/how-do-i-import-my-contacts-in-openerp-18 
https://doc.odoo.com/book/8/8_20_Config/8_20_Config_import_export/ 

Hi Gallo,

            Here what i understand from your question. There is an xlsx file when you add new product in it that needs to be created automatic in Openerp. I have done similar to task to my project if you need help contact m.

skype: george.bics

gmail: george.bics@gmail.com