You can enter the amount on the Foreign Income slip. To do so in TurboTax Online: 

1. Select Find (or the magnifying glass icon) from the top right
2. In the Find window, type in foreign and then choose “Foreign Income” from the list. Then click “Go”.
3. On the “Foreign Income - Summary” page, click “Enter New foreign income for [Your Name]”.
4. Input your information, then click “Continue” to save.