I have found the endpoint from this SO question. But what is the scope need for the same.
I tried these scopes "user.read", "files.read.all", "files.read", "files.read.selected","files.readwrite","files.readwrite.all","sites.read.all", "sites.readwrite.all".
But still getting 403 error. Please find the below screenshot with Modify permission tab in graph explorer.
It might not be enough with the only permission of "Files.ReadWrite" to access Excel Graph requests. As you need to access the file in the SharePoint site, you also need to add another site related permission, e.g., Sites.Read.All.