If you want to change the text only for one product then you will need to add the custom code with the product ID so that it will go only for one and not for all. Also, as the empire is a paid theme so cannot share any code without looking into the theme structure.
If it is possible for you to share your store access with me then I can assist you in making it work for you.
Kindly let me know your thoughts so that we can proceed further on it.
sorry for late reply , actually i have another problem now , i do not know why when i change the theme language to Arabic and adding a product to the cart it's keep loading without any action .can anyone help please ?