where do i enter the activation code for the turbotax deluxe online edition (valid for 8 returns) purchased from best buy.

Hi!

You can activate your prepaid code at turbotax.ca/activation

Follow the steps from this helpful article - https://turbotax.community.intuit.ca/turbotax-support/en-ca/help-article/accounting-bookkeeping/turbotax-online-use-prepayment-code/L9DehX0Qv_CA_en_CA?uid=ma48wk90

Feel free to reach out again if you need further help.