Hi Pavan Kumar Nookala,
Glad to be here and share my suggestion with you.
Per your description, you have a shared Excel file which stores in SharePoint Online library. Users can all update data in this file. Now you want to link this Excel file to Access database which will automatically update when the data change in original Excel file.
After my test, you can try this way to achieve your requirement. When we want to choose the external data source, it will let us Browser from the File Explorer to choose the file. We can sync the SharePoint library use OneDrive sync client. The library will be a folder in your File Explorer like this:
And you can choose the Excel file as External data source by these steps: Create a new database-> External Data-> New Data Source-> From File-> Excel-> And after choose this file’s path-> Select Link to the data source by creating a linked table, and then click OK.
After changing in Excel file online, the Access data will refresh after the file’s syncing process. (You may need to right-click the sheet and choose Refresh link.) That’s the workaround which can achieve your requirement. Hope it can save your time on work.
For the further information, we sincerely suggest you check these articles, you may get some help:
Import or link to data in an Excel workbook (Link to data in Excel part)
Sync SharePoint files with the OneDrive for Business sync client (Groove.exe)
Best Regards,
Ivy