Thank you for reaching out. Because the mandatory deductions are yet to be made, Yes, as you stated, if you've received a T4A from the organization, it means you need to report your income as either 'Self-employment income' or as 'Other Income'.
a) If you're filing as Self-employed:
You need to fill the Form T2125- Statement of Business Activities and enter the eligible expenses to make your gross income to Net Income.
b) If you're filing as other Income:
You need to simply find the T4A slip in TurboTax Online and fill in the details as per your received T4A in the appropriate Box.
For more help, read Guidelines for Self-Employment Reporting by TurboTax.
Here are expenses you can claim for Working from Home.
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