If the T4 from your employer is for the same line of work as your self-employment, you can include all your expenses in your self-employment statement, this is the easiest choice.
If it's a completely different line of work, you may choose to report on both T2125 and Employment expenses. And make sure you don't claim twice for the same expenses.
For more information how to claim Employment expenses in TurboTax Online, please click:
TurboTax Where do I claim my employment expenses in TurboTax Online?
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