I would really caution against taking online art classes. In my experience, it is better to either read on your own and try to paint, or to enroll in a proper art school with face to face classes. Online classes are kind of an unproductive middle ground.
They are good because they get you painting and that spark can be hard to find. But you never get any real instruction or feedback. Watching internet videos is just not the same as watching a person paint, seeing the painting come together before you. There is something fundamental that is lost.
You also do not have the chance to interact with other students in a meaningful way. In traditional art classes this can be a huge source of creativity and drive.