For your application to be confirmed by the Canadian government, you need to have/do the following.
Note that you can only apply for one person at a time regardless of whether you’re related or not.
If you’re included in this group, you don’t need to apply for eTA.
When your eTA application is approved by the Canadian government, you’ll be notified via an approval email sent to your email address. Your eTA will be linked to your passport and stored in the authority’s database.
You’ll need to present your passport to airline staff, and other requiring authorities at checkpoints each time you want to board a flight to Canada.
Note that your eTA is valid for up to 5 years or it will be invalid the day your passport becomes invalid. Your eTA authorises you to visit and stay in Canada for up to six months. If there’s a need for you to stay longer in the country, you must apply for an extension.