It is possible, but only if you have the necessary skills. But I don't recommend you completely abandon official work. No one knows what will happen with bitcoin in the future. You risk to remain without money and pensions. You will agree with me it is very risky.
It can be. But you have to consider things if you are going to change Bitcoin over your job. Because if you are the bread winner of the family and if anyone depends on you, your income here will never be enough to provide the basic needs. I guess you can do both in a same time.