Unable to find out how to configure radio buttons

I just purchased the fundraising plug-in. I have configured the fundraising as well as the settings and selected simple donations.
I need to have several donation levels together with their rewards and I was inspired by the screenshot on this page https://premium.wpmudev.org/project/fundraising/ next to the goals and rewards paragraph. It showed radio buttons with several amounts and the respective rewards.
However I have not been able to find out anyway to have such buttons appear.
The only buttons I can have are either the classical PayPal buttons or some more discreet square and grey donate buttons.
Could you please inform me as soon as you can how this can be done?
But thanks in advance