Ready API OAuth 2 , get Access token and refresh tokne

Hi All ,

I am new to Ready API and learning Automation of OAuth2 Authentication 

I have two pages , where i get the user id and password , following another page where i need to select radio buttons , select a check box and click submit button.

I am able to get the elements in home page where i give the username and password , click submit button.

code for page 1 :

document.getElementById("username").value = "username";
document.getElementById("password").value = "password";
document.forms[0].submit();

Now comes the problem 

On the consent screen , i am not able to detect any elements using Java script. Either the script is executing before the page is loaded or its not able to get the elements.

Earlier i used to get document object as null , which means the script is executed before the page is loaded. Now i dont see that error but it doesnt do anything as well.

var path = "//html[1]/body[1]/div[1]/div[1]/div[1]/div[1]/li/div[1]/img[1]/@src";

//var img = document.getElementByXpath("//html[1]/body[1]/div[1]/div[1]/div[1]/div[1]/li/div[1]/img[1]/@src");
document.evaluate(path,null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue;
img.click();

Also where can i see any logs which i write in console log in Ready API for Java script .. Please let me know how to proceed