Do you have to know how to sing and/or dance in order to market your artwork successfully? I don't know how to sing and dance.?

It's impossible to get paintings into galleries unless you have a degree from an art school, preferably one with some prestige. Of course, having a critic on your side helps a lot. The Pre-Raphaelite Brotherhood got nowhere until John Ruskin's letter to the London Times made all their critics reconsider them. The years in which these painters did their song and dance routine in Victorian music halls got them nowhere, but the myth that singing and dancing is good for a painter's career persists. If you don't believe me, think about Vincent Van Gogh, who dazzled audiences with his vaudeville routine but never sold any paintings.

Below: Pre-Raphaelite documentary, Van Gogh performing

https://www.youtube.com/watch?v=FkWONORqHZw

https://www.youtube.com/watch?v=bPmBPvHzF2c

I can sing, but i dance like a pregnant Walrus.