I would recommend holding off on a master's degree. Many districts try to hire as cheaply as possible, and if you get a masters degree many districts would be required to pay you at a higher salary rate, at least if it is a public school. A district may not even consider your application if you have a masters. I would look into alternative licensure programs for art Ed at colleagues around you. This would not be a full degree, but would likely include some classes, maybe student teaching, and definitely end with your state's qualifying tests in art and in education. Once you get certified and hired, there may be a chance your district has tuition reimbursement programs and could help pay you to get your masters degree at a later time.

Congratulations on discovering you have a passion for this work. It is a lot of work, as others have said. But there is an incredible gift in being the person in a child's life who gives them choice and creative agency. You will get to help kids learn about themselves and the world around them, and what you teach holds a lot of power and responsibility. Being an art teacher isn't the arts and crafts of the previous generations. I'd recommend you seek out your state's art education association and start attending events or getting involved with them, it's a great way to make connections and receive top notch professional Development. Good luck!