To be able to claim a GST rebate, you will first need to register for the GST/HST. Steps on how to register will be given here through the CRA website. To have a better understanding of your GST/HST obligations as a Self-Employed individual, I will recommend you review the following link from the CRA - GST/HST and Commercial Ride-sharing Services
TurboTax also has more information at the following link. Did You Know You Can Claim The GST/HST Rebate On Your Expenses?
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