Need some help using setting variables to determine which cells I want to select in my range - excel

Question

The amount of cells in my data table changes every week so I'm using a count function to determine the number of cells with data then using that count as a variable to put into my range(cells(x,x),cells(x,x) function to select. But I'm having an issue with taking the count and converting it to a variable to use. This is a basic macro I'm putting together for something else i'm doing.
Sub format_table()
Dim x As Long
Dim y As Long
''count the number of rows in rawdata table
Dim LastRow As Integer
With ActiveSheet
LastRow = .Cells(.Rows.Count, "A").End(xlUp).Row
End With
x = LasRow
''count the number of columns in rawdata table
Dim LastCol As Integer
With ActiveSheet
LastCol = .Cells(1, .Columns.Count).End(xlToLeft).Column
End With
y = LastCol
'''use the counted cells to determine a range to select
ActiveSheet.Range(Cells(1, 1), Cells(x, y)).Select
End Sub

Answer 1

I think you are having trouble trying to get the column number as the correct letter, right? Try something like this:
Sub Test()
Dim wb As Workbook
Set wb = ThisWorkbook
Dim ws As Worksheet
Set ws = wb.Sheets("Sheet1") '(replace with whatever sheet name is)
Dim lastRow as Integer, lastCol as Integer, lastColLet as Integer
'get the number value of the last row and column
lastRow = ws.Cells.Find("*", SearchOrder:=xlByRows, SearchDirection:=xlPrevious).Row
lastCol = ws.Cells.Find("*", SearchOrder:=xlByColumns, SearchDirection:=xlPrevious).Column
'uncomment the debug.print statements to see what it's getting for last row/column
'Debug.Print lastRow
'Debug.Print lastCol
'get the letter that the column number corresponds to
lastColLet = Letter(lastCol)
'Debug.Print lastColLet
ws.Range("A1:" & lastColLet & lastRow).Select
End Sub
Function Letter(ByVal lngCol As Long) As String
Dim vArr
vArr = Split(Cells(1, lngCol).Address(True, False), "$")
Letter = vArr(0)
End Function
It uses the function found here: Function to convert column number to letter? in order to convert the column # to a letter, then you can concat the letter and last row to select the way you wanted.

Answer 2

I guess your real issue is to decide what cells you actually need to select
your approach assumes that the left-upmost data cell is always in cell(1,1) and the down-right one is in the intersection of:
last non empty row in column 1, last non empty column in row 1
should that be the case, then you can go on with your code provided you change x = LasRow to x = LastRow...
should not that be the case then you could assume that the range is the one delimited by:
first non empty row in column 1, first non empty column in row 1
last non empty row in column 1, last non empty column in row 1
then you could use this code:
Function GetData() As Range
Dim firstRow As Long, firstColumn As Long
Dim LastRow As Integer, lastColumn As Long
With ActiveSheet
firstRow = .UsedRange.Rows(1).Row '<--| get first used row index
firstColumn = .UsedRange.Columns(1).Column '<--| get first used column index
LastRow = .Cells(.Rows.Count, firstColumn).End(xlUp).Row '<--| get the first used column last non empty cell row index
lastColumn = .Cells(firstRow, .Columns.Count).End(xlToLeft).Column '<--| get the first used rows last non empty cell column index
'return the range
Set GetData = .Range(Cells(firstRow, firstColumn), Cells(LastRow, lastColumn))
End With
End Function
and exploit it in your main code as follows:
Sub format_table()
With GetData '<-- use With-End With block to reference wanted object (Range) and avoid Select/Selection/Activate/ActiveXXX
'format the referenced range
.Font.Name=..
.Interior.Color=..
End With
End Sub
but the GetData() function may still be not the one you need, should data be "jagged" in columns and or/rows with first row/column not hosting the last column/cell
so maybe you simply need:
Sub format_table()
With ActiveSheet.UsedRange
'format the referenced range
' .Font.Name=..
' .Interior.Color=..
End With
End Sub