Hi
It is possible to get a job offer before arriving, but you cannot work and the employer can't pay you until after you land and get your social insurance number. Therefore it's difficult to get a job offer before landing. It depends on your skills and whether the employer really wants to take a chance on someone who hasn't landed yet. And even if they do, what's to stop them from giving the job to someone else they find a week later? That said, the Vancouver job market is very soft right now. There are help wanted signs posted at businesses all around town. So if there were ever a chance to get a job offer before arriving, now would be the time.
You could find a place to live before arriving, but it depends on the landlord and/or rental agency. Some will definitely require you to have landed before signing a contract, as it will be hard to enforce the contract if you don't land due to unforseeable circumstances. You see the dilemma, right? But if you rent a room in someone's house or a basement apartment, the approval process will be much easier. Private homeowners usually scrutinize tenants much less carefully and might not care whether you've landed yet.
Good luck with whatever you do.
TG
I hope that the OP realizes you can't just move permanently to Canada without going through the Immigration system, unless of course s/he is a Canadian citizen.
PMM