Description of Line 8811 as per CRA: You can deduct the cost of items the business used to provide goods or services, for example, drugs and medication used by a veterinarian or cleaning supplies used by a plumber. If you run a daycare, these include household supplies that children use and food you buy to feed the children.
To enter supplies in TurboTax Online:
Select Income > Self-Employment > Business or Professional Activities.
Click Enter New Business for [Your Name] or click Edit beside the business that you have entered previously.
Click Business Expenses and select Continue.
Click Continue until you reach the page "[Your Name], did you pay for office supplies?", Answer "Yes".
Enter the supplies expenses in the column Total cost for other supplies.