I'm self-employed and have a non-capital loss from leveraged trading. Since my business revenue cannot be negative, how would I file my loss? Do I file as other expenses?

As per the Canada Revenue Agency(CRA), you have to file your income tax as a Self-Employed only. you can refer below the CRA and TurboTax links for more detail:

Self-employed Business, Professional, Commission, Farming, and Fishing Income: Chapter 6 – Losses - ...

The Beginner's Guide to Self-Employed Taxes | 2022 TurboTax® Canada Tips (intuit.ca)

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