If your business-use-of-home expenses are causing a loss to your business overall, your net business income will be zero - not a loss. Business-use-of-home expenses cannot make or increase a loss. The amount of your home office expenses applied will be enough to bring your net income to zero. The remainder will be carried forward for future use.

When you transfer your details into your tax return next year using TurboTax, the carried-forward expense will be included and applied if your business has enough income to use it.

https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/sole-proprietorships-partners...