How to file as Etsy artist but also jointly...

So I’m wanting to kick off a small business on Etsy in 2021 selling my art. I know that I have to file/pay quarterly, but I don’t expect this to make more than a few hundred my first year. Should I still file quarterly?

Also, I still want to file jointly with my husband since we have a child. Will I add my income to his when we file jointly even though it’s already been taxed/paid?