Finding multiple cell values from list - excel

Question

I have a workbook with 2 sheets.
Sheet1 contains a list of Product Codes in column A and Column R is Current Stock Level.
Sheet2 contains a list of Product Codes in column A and Column B contains the New Stock Level.
What I want to do is replace the Current Stock Levels in Sheet1 with the New Stock Level from Sheet2.
I found some code on this site already (below) which I have adapted slightly for my purpose and it works fine but only for one Product Code (as it references A1 and B1). What I would like to do is add a Loop so it works down all products in Sheet2 but I'm not sure how to and haven't been able to adapt any similar loops I've found online for this purpose.
Any help would be appreciated, my backup plan is to just do a v-lookup in Sheet1 to bring in the Sheet2 New Stock Level values and then replace the original column but I would like to get this other way working if possible.
Private Sub CommandButton1_Click()
Dim search_range As Range, search_value As Range, _
lastcell As Range, foundcell As Range
Dim ws As Worksheet
Set ws = ThisWorkbook.Sheets("Sheet1")
Set search_range = ws.Range("A1", ws.Range("A" & Rows.Count).End(xlUp))
Set lastcell = search_range.Cells(search_range.Cells.Count)
Set search_value = ThisWorkbook.Sheets("Sheet2").Range("A1")
Set foundcell = search_range.Find(What:=search_value, After:=lastcell,
LookIn:=xlValues, _
LookAt:=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
MatchCase:=False, SearchFormat:=False)
If Not foundcell Is Nothing Then foundcell.Activate Else MsgBox "Not Found"
ActiveCell.Offset(0, 17).Value = Sheets("Sheet2").Range("B1").Value
End Sub

Answer 1

How about the following:
Private Sub CommandButton1_Click()
Dim search_range As Range, search_value As Range, lastcell As Range, foundcell As Range
Dim ws As Worksheet
Set ws = ThisWorkbook.Sheets("Sheet1")
Set search_range = ws.Range("A1", ws.Range("A" & Rows.Count).End(xlUp))
Set lastcell = search_range.Cells(search_range.Cells.Count)
For i = 1 To lastcell.Row
Set search_value = ThisWorkbook.Sheets("Sheet2").Range("A" & i)
Set foundcell = search_range.Find(What:=search_value, After:=lastcell, LookIn:=xlValues, LookAt:=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext)
If Not foundcell Is Nothing Then foundcell.Activate Else MsgBox "Not Found"
ActiveCell.Offset(0, 17).Value = Sheets("Sheet2").Range("B" & i).Value
Next i
End Sub

Answer 2

The idea is the following - you have two types of ranges - ranges where you search and ranges where your value should be. They are called Target and Search.
In the code below you loop through all cells in column A of the first worksheets and you look for their value in column A of the second worksheet. If you find the value, you write the value in column B of the second worksheet to the 17. column in the first worksheet:
Private Sub CommandButton1_Click()
Dim targetRange As Range
Dim targetValue As Range
Dim searchRange As Range
Dim lastSearchCell As Range
Dim foundCell As Range
Dim wsTarget As Worksheet
Dim wsSearch As Worksheet
Dim myCell As Range
Set wsTarget = ThisWorkbook.Worksheets(1)
Set wsSearch = ThisWorkbook.Worksheets(2)
With wsTarget
Set targetRange = .Range("A1", .Range("A" & .Rows.Count).End(xlUp))
End With
With wsSearch
Set searchRange = .Range("A1", .Range("A" & .Rows.Count).End(xlUp))
End With
Set lastSearchCell = searchRange.Cells(searchRange.Cells.Count)
For Each myCell In targetRange
Set foundCell = searchRange.Find(What:=myCell, After:=lastSearchCell).Offset(0, 1)
If Not foundCell Is Nothing Then
myCell.Offset(0, 17) = foundCell
Else
MsgBox "Not Found"
End If
Next myCell
End Sub