I have us pension income. where do I claim 15% of us income as additional deductions on turbo tax format?

You are looking for the Foreign Tax Credit because we have a tax treaty with the USA to make sure you are not double taxed. 

• This can be found by clicking on the "Find" icon at the top left corner of your screen, type in "Foreign Tax Credit" this will open the screen to claim your 15% of your income.

Remember to report all foreign income in CDN$.