When you post JSON text on the forums, be sure to format it using the </> button in the toolbar above the message area. That allows you to copy & paste it into Best JSON Viewer and JSON Beautifier Online without the smart quotes invaliding the JSON. I reformatted yours already.
You can get the property “response.token” from the object (the object is the green response block).
I have a tutorial that explains all of this in a video: API JSON Tutorial (Video)