I'd be surprised if you could simply read a book or watch a video and learn how to architect complex software solutions, honestly. For me working at different orgs and being curious about how all the various layers of the software stack fits together has given me a decent perspective on different approaches to problems.
Also, "good" here is somewhat relative. Being "good" an architecting problems for large orgs operating at scale is far more challenging than being good at architecting solutions at a small startup.
Smaller, younger companies generally don't need anything super fancy or complex, what's important is getting things done so typically you build simple and worry about doing things right later. Some basic AWS knowledge and a strong coding background is probably all you need.
Larger, older orgs are far more intimidating because there's so much complexity already in place, and often there will be entire teams built around managing that complexity. In these cases you need have an appreciation for what already exists and build things that complement and improve on that. You also need more experience with building at scale. At a small startup whether you decide to go serverless or not doesn't really matter, but at a large org with tens of thousands of daily users the cost of a bad decision grows exponentially.
Another thing I'll note is that if you're doing this for career opportunities whether you can do something doesn't matter one bit. Companies won't hire you unless you have a track record. If you want to become a technical architect I think the challenge is mostly knowing how to play the game in such a way that you can take on those responsibilities at the place you work. Learning how to architect new solutions isn't that difficult if you're curious about how things work.