For “date interest payments commenced” for vehicle- do I enter from the year I purchased car in 2021 or for the beginning of this tax year 2022?

You have to enter the date when you purchased the car that's 2021. For more detail, you can refer TurboTax link: https://turbotax.community.intuit.ca/turbotax-support/en-ca/help-article/manage-expenses/self-employ...

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