when was surafce with serial number 020710481953 purchased

Go to Microsoft Devices and sign in with the Microsoft account associated with the Surface.

Select the Surface with serial number 020710481953.

Check Device info / Warranty & service. The warranty start/end dates can help establish the approximate purchase date.

If the device was purchased through a retailer or organization, the original invoice/receipt is the authoritative purchase date.

Your Microsoft account order history (account.microsoft.com/orders) if you bought it through Microsoft Store