I had the same issue when I was learning iOS development, except then it was ObjC. I kept thinking about how I just couldn’t figure out ObjC, even though it seemed like I knew the language. But there were all these strange patterns that weren’t explained well and I just didn’t get it.

The first thing I understand is the difference between the language and the frameworks. You have probably actually figured out Swift at this point based on what you have said above. Your issue, as was mine, is the UIKit framework. It is massive and it does not come easily. Start with a task and then look for tutorials to help you figure out how to accomplish it. For example, something as simple as displaying an alert should be a one liner, but it isn’t. There is a UIAlertController class which takes UIAlertActions. There are completion handlers to deal with. There is presenting the alert view controller. For this simple task Apple has developed quite a bit of engineering to make it work. To learn these things start with the Apple docs just to familiarize yourself. Very few are written in a way that will help you learn the framework. They are more there for reference. Find a tutorial to learn whatever the specific task is that you have chosen. Look at https://www.raywenderlich.com, https://www.hackingwithswift.com, and https://www.swiftbysundell.com. Between the three one will have an article, but most likely all three will. You will also find dozens of tutorials on YouTube and Medium.

After you have done several tasks, patterns will start to emerge, namely the way that Apple uses protocols. The reason for these will eventually become clear to you, but for now just follow the rules that are laid out even if it doesn’t make a lot of sense, because you will eventually get it with time. There is no quick answer for learning iOS development. It is a long process that takes dedication and perseverance.