Unfortunately, you can't upload it into TurboTax Online.
However, You can use the Auto-fill function. CRA’s Auto-fill My Return automatically fills out part of your tax return by importing your information and slips from your CRA My Account. The benefits of this feature are supported by all editions of TurboTax Software at no extra cost.
To use the Auto-fill my return in Turbotax, please watch
How to use Auto-filling on your return. For more information about Auto-fill, please read
The Complete Guide to Auto-Fill my Return (AFR).
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