Here is the instruction for making a box plot in Excel. 
     Excel Instruction
Excel.         Example 1
Make a box plot of the point distribution of scores on a school quiz:
Excel         and         enter         all         the         data         points         into         a         series         of         cells         across         one         line.         It’s         up         to         you         if         you         want         to         write         them         in         a         row         or         a         column.         
      
      
Add an appropriate title to make the chart even more explanatory. You can also add the axis title “Points” on the vertical axis.
      
The final box plot should look like this: