What's the next level after the Claude Beginner Stage?

I've had the $20/month plan for a while and I'm realizing I'm barely scratching the surface compared to what people in here are doing. My use so far has been pretty basic: assignment trackers for my classes, drafting emails, custom instructions, a few skills built. That's it. Meanwhile I keep seeing posts about workflows, projects, agents, people running whole businesses through it, and I don't really know where to start. Context: I'm an engineering student, about to start a full-time internship in pharma manufacturing, so my free time is about to shrink a lot. Two questions: What's the next level past skills and custom instructions? Specifically about how people chain things together. Such as, projects as persistent workspaces, connectors to calendar/drive/email, using Claude Code for non-code work, agents that run multi-step tasks. Which of these actually changed your workflow vs. which were fun for a week and then abandoned? Anyone turned this into income? I'd like to start a side hustle with limited time and no capital. Not looking for "sell prompt packs." More interested in whether anyone is doing real freelance/contract work where Claude is the leverage and what you'd do differently starting over. If you were a student with a decent Claude setup and about 5-8 hours a week to spare, where would you put that time?