Even if you have no income there are good reasons as to why you should or are required to file an income tax return;
Whatever your residency status in Canada, you have to file a return especially if any of the above criteria apply to you.
If you live abroad but receive income from a business that you own, investments or property you own in Canada you will need to file an income tax return.
There is no age exception - if you meet one of the criteria above you need to file.
Students are not exempt, if you earned over $3500 in 2018 you will need to file a return even if you are still in school.
Even if you are not required to file it is usually in your best interest to file anyway;
From an article by Turbo Tax Feb 2, 2019
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