Я верно понимаю, что хотя личный кабинет завести до подачи первой декларации нельзя, подать первую декларацию онлайн можно?
Can you file your return online if you’ve never filed a return before?
If you never filed a return before, you can file online using NETFILE-certified tax software or through a tax preparer. To be eligible, you must have a date of entry into Canada during the tax year you are filing for. Additionally, you must have one of the following:
a valid social insurance number (SIN);
a temporary social insurance number; or
a temporary tax number (TTN).
www.canada.ca/en/revenue-agency/news/newsroom/tax-tips/tax-filing-season-media-kit/new-canada-filing-taxes-here-are-tips-help-you.html