what IDs are required to start any job ?
Is it possible to start working anywhere as soon as you land ?
I know PR card takes max 4- 6 weeks of time to receive. Is this card necessary to work ?
You need to apply for your SIN. The employer needs it to pay you. You can get your SIN at Service Canada right away. You don't get the actual SIN card for 1 or 2 weeks but there should be no problem starting work right away.