Option Explicit
Sub Macro1()
Dim wsSrc As Worksheet
Dim lngLastRow As Long
Application.ScreenUpdating = False
Set wsSrc = ThisWorkbook.Sheets("Sheet1") '<-Sheet name with the data. Change to suit if needed.
On Error Resume Next
With wsSrc
.ShowAllData
.Columns.EntireColumn.Hidden = False
.Rows.EntireRow.Hidden = False
lngLastRow = wsSrc.Range("A:I").Find("*", SearchOrder:=xlByRows, SearchDirection:=xlPrevious).Row
If lngLastRow >= 3 Then
.Range("J3:J" & lngLastRow).Formula = "=TEXTJOIN("""",TRUE,A3:I3)"
'Use (uncomment) the following two lines if you want only the values of the formulas to remain
'wsSrc.Calculate
'.Range("J3:J" & lngLastRow).Value = .Range("J3:J" & lngLastRow).Value '<-Use this if you want the values of the formula to show only.
End If
End With
On Error GoTo 0
Application.ScreenUpdating = True
End Sub