The deadline for filing your 2020 taxes in Canada for most people is April 30. (deadlines differ for other circumstances, details here)
If you haven’t filed yet, keep in mind that you can claim some expenses if you worked from home last year due to the pandemic.
If you worked more than 50% of the time from home for at least 4 consecutive weeks, you can claim $2 for each day.
The maximum amount that can be claimed is $400/person.
You must meet the eligibility criteria, you can confirm that here.