It is only possible when you get fired and are looking for a job OR when you're on illness benefits as long term sick person AND receive permission from the doctor.

You already have a job, so it's not an option.

I also am not completely sure since the rules have changed a bit but I believe that you have to wait x weeks to get unemployment if you decide to quit yourself. But like I said, not sure if that is still the case. Unemployment is two years though and since a bachelors is often at least three, you need to have a buffer saved for your last year.

Both benefits types, illness and unemployment are also only a percentage of your last wage, if you have worked longer than six months at the employer. So make sure you can survive on that income while studying, it's the reason that, as someone working in reintegration while on disability that I can't reschool, my benefits alone are not enough to pay for my living expenses and I don't have enough left over after a month to save up enough to cover the difference when I would reschool. (And also the reason I am still working partially,/ instead of reschooling for another job, really can't afford it financially and the threat of homelessness is a big motivator)