How do I show a summary of the results in graph form for each question

It is possible to create reports and visualize your submission data in graphs with the help of jotform's report tool.You can also find more information in the guide given below.

https://www.jotform.com/help/187-How-to-Create-a-Visual-Report-with-Your-Form-Submissions

If you need help at any step, feel free to contact us.