Since the first announcement of SwiftUI, a ton of great quality content has been posted on getting started with Apple's new Declarative UI framework that'll run on iOS, macOS, watchOS & iPadOS.
Originally posted on GitHub, here's a list of great quality tutorials/videos on SwiftUI 🙌

SwiftUI on Apple Developer Documentation

📹 Keynote WWDC 2019 - First announcement of SwiftUI

📹 Platforms State of the Union 2019 - More SwiftUI

📖 Apple Developer Tutorial on SwiftUI

📹 Introducing SwiftUI: Building Your First App

📹 SwiftUI Essentials WWDC Video

📹 Building Custom Views with SwiftUI

📹 Integrating SwiftUI

📹 Data Flow Through SwiftUI

📹 Mastering Xcode Previews

📹 Accessibility in SwiftUI

📹 SwiftUI On All Devices

📹 SwiftUI on watchOS

Paul Hudson on Hacking With Swift

📖 First look at SwiftUI

📖 Getting Started with SwiftUI

📖 Quick Start Guide on SwiftUI by Hacking With Swift

📹 SwiftUI by Example Videos

📹 Build a dynamic list app with navigation and images

SwiftUI Tutorials by Lets Build That App

📹 SwiftUI Sneak Preview Demo Project

📹 How to Run SwiftUI on Mojave with Playgrounds and Sample Code

📹 SwiftUI Basics: Dynamic Lists, HStack VStack, Images with Circle Clipped Stroke Overlays

📹 SwiftUI: Facebook Complex Layouts - Horizontal Scroll View

📹 State Management and Bindings

📹 Fetching JSON and Image Data with BindableObject

SwiftUI by John Sundell

📖 A first look at SwiftUI: Apple’s declarative new UI framework

📖 Answers to the most common questions about SwiftUI

📖 SwiftUI’s relationship to UIKit and AppKit

SwiftUI Tutorials by Code With Chris

📹 SwiftUI Basics Tutorial

📹 SwiftUI App Tutorial - Lists, Navigation and JSON Data

📹 How To Handle User Input

SwiftUI Tutorials by Kilo Loco

📹 SwiftUI Presenting Data In A Scroll View & List

📹 Intro To SwiftUI: Simple State Management

📹 Before You Learn SwiftUI, You Need To Hear This...

📹 Using Both UIKit And SwiftUI In Your Project

SwiftUI by Rebeloper

📹 SwiftUI = Mind-blow | WWDC iOS developer reaction

📹 SwiftUI - DON'T LEARN IT (JUST YET)

📹 SwiftUI Beginner Tutorial On iOS 13 by Devslopes

📹 Simple SwiftUI App by Brian Advent

💻 An example to-do list app using SwiftUI

📖 Inside SwiftUI's Declarative Syntax's Compiler Magic

💻 All of the Apple documented SwiftUI tutorials in one easy download

📹 Live Coding SwiftUI by Swiftly Tilting Planet

SwiftUI by Maxcodes

📹 What is SwiftUI?

📹 How To Create Views, Text and Stacks

📹 Creating NavigationView, List, Text, NavigationBarTitle

📖 SwiftUI Cheat Sheet

SwiftUI by Gary Tokman

📹 SwiftUI Tutorial - Build a list that fetches JSON!