I think you need to figure out a project first.

No point in saying I’m making an app, use Swift then realize that you needed Objective C since the app was a game.

You also want to look at your coding preference, and existing frameworks.

Node and React is a perfect and quick way make simple web based apps that work on iOS, while also giving your self the opportunity to learn how to use xcode and swift if you need native call functionality.

Unity, Unreal and GoDot are all gaming frameworks that have iOS build support. Again with xcode and Objective C native call support. I think swift also works but I never got it to work 😅.

The project determines the framework, the framework determines the coding language. And yes making a native iOS project counts here too if you feel its the best fit for your project.

Hacking with Swift is a great resource. They have quite a few books related to development in Apple platforms (some free). You’ll probably want to do some research on if you want to learn SwiftUI or UIKit. UIKit is still used much more frequently in industry, but SwiftUI is becoming more mainstream, and is easier to learn. Hacking with Swift has books for both frameworks.

Personally, I’d recommend just jumping into writing a simple app (probably by following along with a tutorial) since you already know how to code, and have a grasp of the basics of Swift. There isn’t too much you need to learn about Xcode initially, and any tutorial for creating your first app should walk you through any Xcode specific steps you do need to do. Most of your learning will probably be related to either UIKit or SwiftUI, which are the frameworks you use for actually getting stuff on the screen. While learning these, you’ll undoubtedly pick up more knowledge about Swift and Xcode, which will improve those skills. I certainly don’t think you need to become an expert in Swift or Xcode before learning UIKit or SwiftUI. As you learn more, you’ll learn what areas you need to improve on, and can tailor your journey from there.

The Apple iOS development tutorials are pretty good. It should be your first stop. I doubt you’ll need a second stop.

Best pathway to becoming iOS dev

Be rich. Buy Apple iPhone, Apple Mac, Apple Developer subscription. Put together app, upload app. Done.