If you withdrew money from an RRSP, then you should have received a T4RSP slip.
You can enter a T4RSP slip in TurboTax Online by doing the following:
Click on Find (magnifying glass) in the top right-hand corner. Type "t4rsp" in the box, then select "T4RSP Income from an RRSP" from the list and click “Go”.
Click the “Enter New T4RSP for [NAME]” button, and then enter your information.
Click the “Done with T4RSP” button, to save your information.