Thank you for the question.
If you owe taxes for the tax year 2020, made less that $75,000 in 2020 and received CERB, then there.... However, you must still file your taxes for 2020 by the due date of April 30, 2021 or you run the risk of being hit with a failure to file penalty.
However, while you won't be charged interest on your 2020 tax balance until 2022, you should still pay the amount ASAP.