If you are trying to connect to the excel file in the sharepoint you can use it in a connector like following
let
Source = Excel.Workbook(Web.Contents("https://abc.sharepoint.com/teams/Analytics/Shared%20Documents/Folder/subFolder/file.xlsx"), null, true),
Finance_Sheet = Source{[Item="Finance",Kind="Sheet"]}[Data],
#"Promoted Headers" = Table.PromoteHeaders(Finance_Sheet, [PromoteAllScalars=true])
in
#"Promoted Headers"
If you want to connect only to the sharepoint site and select later within the query, you can use the following conncetion
let
Source = SharePoint.Files("https://abc.sharepoint.com/teams/Analytics", [ApiVersion = 15])
in
Source
In the latter approach the trick is not use the full path of the file but only the root URL