Excel VBA Copy specific Column from different Worksheets - vba

Question

I'm currently developing a monitoring Tool in Excel using VBA and encountered some difficulties when copying data.
Current Code:
Sub CopyID()
'Copies entire Row of IDs from "Sheet 2" to main Sheet "Main Sheet"
Dim lastCell As Long
LastCell = Cells(Rows.Count,'Sheet 2':M).End(xlUp).Row
'Missing here: Copy to Column 1 at Row 3!
Sheets("Sheet 2").Columns(M).Copy Destination:=Sheets("Main Sheet").Columns(1)
End Sub
What it is supposed to do:
Copy the Data of Sheet2_Column M starting at Row 2
to
Main Sheet Colum A sarting at Row 3
Also, I don't know if this is possible yet, use a specific formula for the destination (Formular is: =LEFT(Data,10))
I am glad for any response to this as I'd like to learn how these "Copy Methods" work in detail and am happy for any tipps and tricks regarding these methods.
Edit//
The Copy Part should work like this
Sheet 2 Contains a Colum that has a headercell and X cells with a value that has a similar format.
Example of the Sheet 2 Contents
This is a row in Sheet 2. I only need the first 10 digits of the content of the cells. Is it possible to include that as a formula similar to
=Left(Sheet 2:M2,10)
so it works like this:
"sheet 2" cell content: "1234567891_1_123X" copy to "main sheet" as "1234567891"

Answer 1

Define your source and destination worksheet. And range/column names bust be submitted as strings like "M".
Sub CopyID()
'Copies entire Row of IDs from "Sheet 2" to main Sheet "Main Sheet"
Dim WsSource As Worksheet
Set WsSource = ThisWorkbook.Worksheets("Sheet 2")
Dim WsDestination As Worksheet
Set WsDestination = ThisWorkbook.Worksheets("Main Sheet")
Dim lastRow As Long
lastRow = WsSource.Cells(WsSource.Rows.Count, "M").End(xlUp).Row
'Missing here: Copy to Column 1 at Row 3!
WsSource.Range("M2:M" & lastRow).Copy Destination:=WsDestination.Range("A3")
End Sub
Edit:
To copy only the first 10 characters of each cell would need a process for each value:
Option Explicit
Public Sub CopyID()
'Copies entire Row of IDs from "Sheet 2" to main Sheet "Main Sheet"
Dim WsSource As Worksheet
Set WsSource = ThisWorkbook.Worksheets("Sheet 2")
Dim WsDestination As Worksheet
Set WsDestination = ThisWorkbook.Worksheets("Main Sheet")
Dim lastRow As Long
lastRow = WsSource.Cells(WsSource.Rows.Count, "M").End(xlUp).Row 'Find last row in column M
Dim ArrSource As Variant
ArrSource = WsSource.Range("M2:M" & lastRow).Value 'read column m values into array
Dim i As Long
For i = 1 To UBound(ArrSource) 'process each value in the array
ArrSource(i, 1) = Left$(ArrSource(i, 1), 10) 'keep only left 10 characters
Next i
WsDestination.Range("A3").Resize(UBound(ArrSource), 1).Value = ArrSource 'write array into destination
End Sub
Note .Resize(UBound(ArrSource), 1) defines the destination the same size as the array is that we want to insert.