I think it is essential to understand how the arrays work in Excel
Input data or observed values are located in an abitrary number of rows and normally in only one column, but no problem in using more columns as well. In your example in the A column

Bin range in one column only. The bin range should range from the minimum observed to the maximum observed value in steps of something reasonable. In your case the range should be 0,1,2,3...25 (or if that gets too detailled try 0,2,4,6...26). In your example in the B column

Frequency in the column adjecent to the bin range, in your example the C column.
1. In cell C1 write =FREQUENCY(A1:A13,B1:B25)
2. Mark the all the cells adjecent to the bin range, i.e. C1 to C25
3. Press CTRL+SHIFT+ENTER

You should note that it is not possible to reduce the length of the array if you e.g. chose a shorter bin range; you wil have to rewrite it, but you can always expand. Just select the complete new range where you want the frequency and press CTRL+SHIFT+ENTER

Note if you choose to illustrate it with a column graph: The column on the graph indicating 2 observations with the value of 11 and the label 11 just under the center of the column actually indicates two observations with values between 10 and 11. The label 11 should rightly be at the right edge of the column, but this is not how Microsoft works.

Another important thing: In this example your figures are pure integers, but somtimes integer-looking figures are the result of calculations and by the not-always-so-lucky combination of Microsoft and Pentium this can lead to false results. You can see e.g. the figure 12 repeated 7 times, but the analysis reveals only 6 observations between 11 and 12. This is because one of the 12's is actally 12.00000000000001 and therefore ends up in the 13-bin.