Dear Cuong Dang Quoc,
Greetings! Thank you for posting in Microsoft Community. We are happy to help you.
As per your description, you created Rating questions with Number symbol in Forms, you want to know if there is any method to automatically sum total in Microsoft Forms.
May I know if my understanding of the scenario is right?
If yes, we're sorry and we're afraid there is no out of box way in Microsoft Forms to achieve this requirement. Currently, we need to use formula in the exported Excel file to get sum total.
We do understand the inconvenience caused and apologize for it.
However, per our search, Power Automate flow may achieve your requirement, here is a similar thread: Solved: Sum form entries for logic? - Power Platform Community (microsoft.com)
If you are willing to know more about flow solutions, considering that we have a dedicated channel Microsoft Power Automate Community, to make sure you get the dedicated assistance, I sincerely recommend you go to that community and post a new question, members and engineers are more professional with this kind of questions and will help you further.
If our understanding of the scenario is different from yours, feel free to point it out, we will continue helping you.
Thanks for your cooperation and understanding! Hope you have a nice day!
Sincerely,
Tina | Microsoft Community Moderator