Comment by obj-g

No, you're almost always allowed to work while waiting for the visa to be approved (which it will be if everything is in order from the start). In other words, once you have a job offer you can apply for a work visa, and once the application process has begun you can start working. It's also pretty easy to set yourself up as a freelancer in many European countries but you have to do more things on your own (taxes, etc).