I have a
I have a question though, What if i give my friend's address where i am planning to quarantine in his apartment?.Is that possible?.Do i have to give a letter from my friends saying he's ready to provide essentials and groceries?It all depends upon immigration officer. As per some landing experiences posted on this thread immigration officers just asked for quarantine address and plan for getting the groceries and medicines without going into too much details. If the house has separate entrance for you then I don't think your brother needs to leave the house. Lot of people have quarantined at their friends and relatives house.
For your own satisfaction, you can keep Plan B with you of making your brother and his family to leave the house for 14 days. If officer gets into too much details regarding your quarantine stay then initiate Plan B.
When Canada is gonna open border for Tourists? Good question. I guess we need to wait for vaccine to come out.
Can your parents travel as immediate family members after you activate your PR status upon landing? Immediate family members of PR holders are exempted from travel restrictions.