Sub Demo()
Dim strDate As String
Dim res
strDate = "07/10/2019 08:53:03 IST"
res = Replace(strDate, " IST", "")
res = CDate(res)
Debug.Print res
End Sub
If you need further help, I'd recommend that you upload sample workbook.
You could also do this with Power Query. Load the table to PQ. Split the column on the right most space. Delete the column you just created holding only the value IST. Load the table/query back to your excel sheet.