Is there a way you can do both (stay at your stable but boring job for now AND make art)? I say that bc it may not serve you financially to just up and quit. But you could plan for it.

In terms of making money through illustration, this society doesn't often reward artists (I'm an artist type too btw and its something I'm well aware of). But yes, it could be done, imo. You say you don't know where to start in making money through your art. Why not start here: research what it would take to make money with your art. What would you have to do? How would you do it? Would you have to hone your craft? Make a portfolio? Network w people? There are books out there as well as many online articles on how to do this. You could make an etsy shop and sell your work there, too.

Also have you thought about artistic jobs like graphic design?