Framer prototypes are compatible with three user testing platforms, UserZoom, UserTesting, and Lookback. To test your prototype on these platforms all you need to do is get the share link from your prototype and head to the platform of your choice.
Once you have a prototype that you want to user test there are two things you need to do. First select the initial screen of your prototype on the canvas and set it to Responsive Mode in the preview menu.
Next, you can get the correct link of your prototype in the preview by clicking on Copy Link in the upper right hand corner of your preview. Anyone will be able to view the prototype in fullscreen by clicking the expand icon in the Prototype View.
Now that you have your link correctly set up, head to UserZoom, UserTesting, or Lookback and start your user testing sessions.