Do I enter my payment for 45 hours as working as a contract for office relief

It would depend. If you received a T-slip for this employment income, then you would need to enter the slip first. Then, depending on what information is on the slip, you may also need to fill out the Self-Employment form (T2125). This TurboTax FAQ has more information: Why is TurboTax telling me I'm self-employed?

If you didn’t receive a T-slip, you can enter this amount as “Other Employment Income”. To do this in TurboTax Online:

1. Open your TurboTax return. At the top of the page, click the "Find" icon.
2. When the search bar appears, type in “tips”, select “Tips, Gratuities, and Other Employment Income” from the list, and then click the “Go” button.
3. This will take you to the Other Employment Income Sources page. Here you can enter any employment income that you earned but didn’t get a T-slip for. 
4. Click the Continue button to save your work.

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