Start with the language document, and with a Swift Hello World program, or similar.
Also start with Playgrounds and its Swift tutorials, and not Xcode: Swift Playgrounds - Apple Developer
Playgrounds are intentionally simpler than Xcode. But Playgrounds are very capable, and very useful. Why Playgrounds first? Learning both Swift and Xcode at the same time is a much larger effort, and learning Swift first will get you productive more quickly. (I use both Xcode and Playgrounds.)
As for learning more about the Swift language and syntax (in addition to the tutorials online), here is a (free) Apple book:
https://books.apple.com/us/book/the-swift-programming-language-swift-5-7/id881256329
If you’re just starting out with programming more generally:
Learn, Build, and Innovate - Apple Developer
Here are a Stanford iOS Swift course and a Harvard Python course (both are college level courses, and free):
… https://cs193p.sites.stanford.edu/
… https://pll.harvard.edu/subject/python
Keith has previously suggested Big Nerd Ranch books, in another reply:
https://bignerdranch.com/books/