What programming language to learn next?

[CathyRoberson]

Hello, I'm basically a writer but currently learning programming to create my own e-commerce website. I'm a beginner and I've already finished learning the basics of HTML and CSS. Now, I just wanted to know what programming language I should learn next? Is there a programming language that isn't too much harder than HTML and CSS and also is relevant to e-commerce web development?

Thank you!