First, add a reference to Microsft excel object library and then try this source code:
Option Explicit
Private Sub Command1_Click()
Dim xlTmp As Excel.Application
Dim wb As Workbook
Dim ws As Worksheet
Dim var As Variant
Set xlTmp = New Excel.Application
Set wb = xlTmp.Workbooks.Open("MyXL.xls")
'Specify your worksheet name
Set ws = wb.Worksheets("Sheet1")
'For READING CELL
var = ws.Range("B3").Value
'or
var = ws.Cells(2, 3).Value
'FOR WRITE CELL
ws.Cells(1, 1).Value = "My text"
ws.Cells(2, 1).Value = "1234.56"
wb.Close
'or ws.SaveAs("C:\\myDocument\myNewXL.xls")
xlApp.Quit
Set ws = Nothing
Set wb = Nothing
Set xlTmp = Nothing
End Sub