Hi Nitesh,
Sorry to hear that you're experiencing this issue!
I am Bhavik, a Microsoft user like you. Please note, I am not a Microsoft employee and don’t have direct access to your account, but I will do everything I can to help you with your queries. :)
Is this file created by you?
Looks like the file is not the Excel file or it is corrupted due to some issue.
Have you faced any recent abrupt shutdown while working on this file and then this message started appearing?
Also, please try to open Excel in safe mode and then try to open this file from File > Open.
To open Excel in safe mode, execute below command in Run Window (Windows + R)
excel /safe
Let me know in case of any further assistance is required, I will be glad to assist.
Thanks
Bhavik