Do I pay taxes if I sell online?

Hello, I'm interested in understanding the tax implications of selling items online. I've been reading about cryptocurrencies and their role in the digital economy, and I'm wondering if the same principles apply when it comes to selling goods or services through online platforms. Specifically, do I have to pay taxes if I sell something online, and if so, how do I go about reporting those earnings? I'm looking for clarity on the tax regulations surrounding online sales, especially in the context of cryptocurrency transactions. Can you provide me with some guidance on this matter?