From Easy step click on Forms and then the bottom left side there is "Forms" click and select T1 General Forms.

The scroll to line 256 and double click, this will take you to Additional Deductions and the line is called "Other income exempt under a tax treaty" and you can manually enter it there. 

Read more in this article: https://turbotax.intuit.ca/tips/what-is-exempt-foreign-income-6233