If you use a motor vehicle for both employment and personal use, you can deduct only the percentage of expenses related to earning income. To support the amount you can deduct, keep a record of both the total kilometres you drove and the kilometres you drove to earn employment income. The CRA considers driving back and forth between home and work as personal use.
https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/tax-return/completing-a-tax-return/deductions-credits-expenses/line-22900-other-employment-expenses/salaried-employees/allowable-motor-vehicle-expenses.html
--------------------
What the CRA considers business-related driving
Business-related driving is considered to be any driving made for the purpose of being able to complete your work-related tasks. These include:
- Travelling between two places of work
- Attending work-related meetings or conferences
- Meeting clients and visiting customers
- Running employment-related errands such as replenishing supplies
Note that commuting from home to your workplace is not considered business driving.
https://www.driversnote.ca/cra-mileage-guide