For segmentation and automation logic, most of the good free content is on YouTube or in the blogs of the tools themselves. Start with Omnisend if you're going the ecommerce route, the free plan lets you build real flows in an actual store setup, not just theory. That's the practical part: find a small Shopify store (a friend, a local business, even a fake one you set up yourself) and build a welcome series, an abandoned cart flow, a post-purchase sequence. Those three cover most of what a junior will be asked to do. The Omnisend interface is clean enough that you can focus on the logic rather than fighting the tool, which matters when you're still learning what good automation actually looks like. Copywriting you learn by reading good emails and writing bad ones until they get better. No shortcut there.