Hello,
I have done several courses on Udemy, by:
Angela Yu
Gwinyai Nyatsoka
Nick Walter
Stephen DeStefano
Rob Percival
Packt Publishing
I still struggled with concepts like delegate, closures. The online Apple orange books fixed it for me. They're great books:
https://developer.apple.com/learn/curriculum/
And I like the online Apple SwiftUi tutorials:
https://developer.apple.com/tutorials/swiftui/
And the Apple online Swift book:
https://docs.swift.org/swift-book/index.html
Thanks,