The formula works the same way as a code, but if you want a code:

Option Explicit

Sub Chnrajmac()
 Application.ScreenUpdating = 0

    Range("C2").FormulaR1C1 = _
        "=IFERROR(INDEX(Sheet2!C3,MATCH(RC[-2]&RC[-1],INDEX(Sheet2!C1&Sheet2!C2,0),0)),0)"
    Range("C2").AutoFill Range("C2:C" & Cells(Rows.Count, 1).End(xlUp).Row), xlFillDefault
 
 Application.ScreenUpdating = True
End Sub