You can find a copy of your submitted T1 General if you have registered for a CRA My Account. Your account should have the records of T1 General for the current year and the past 11 years that you filed under the tax returns view section. Anything older, you will need to contact the CRA directly at 1-800-959-8281 to request a copy.
If you used TurboTax to file your taxes for the year that you need, you simply log onto your TurboTax portal and access the return for the year you are interested in.
Here is a great TurboTax article: How to Get a Copy of a T1 General Return
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