1) Make Excel Sheet Read only.

Review tab -> Protect Sheet.
2) Make your Excel Workbook Partial Protected
i) Select the table -> Right Click -> Format Cells -> Change Protection Check Box.

Review tab -> Protect Sheet. 

3) Protect Structure or Worksheet.

Review tab -> Protect Workbook -> Type Password

4) Set Opening Password

File -> Save As -> (On Save as dialog Box Select Password Option ->Enter the Password -> Re Enter Password -> OK