changing the results visualization (chart type)

Hello @michal hadas! Welcome to the Typeform Community! 👋🏼

I'm afraid it's not possible to visualize the results summary in a pie chart. I believe this article might be helpful for you to learn how to work with your responses. 

Another alternative is connecting your form to a google sheets and then working with excel, creating a pie chart over there. 

Let us know if you have any other questions. Wishing you a great week! 😊