Action Details
Requirements and how-to articles for Apple's action:

Requirements
You need this to get it done:

Pricing
Choose a price tier for your app. (Note: If you don’t have a Paid Applications agreement, you can only choose a free price.)
Availability
You can select the territories where you want your app to be available on the App Store. By default, all territories are selected, but you can deselect territories where you don’t want your app for sale. (Note: You must set a price for your app before you can edit territories.)
App Build
Each app can have multiple versions, and each version can have multiple builds. To publish your app on the App Store, you must choose which build to submit to review.
Your app’s total uncompressed size must be less than 4GB. (Apple Watch apps must be less than 75MB.)
The maximum executable file size is 500MB for iOS 9.0 and later and tvOS 9.0 and later, 60MB for iOS 7.X through iOS 8.X and 80MB for every version earlier than iOS 7.0.
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How-To Articles
A list of useful links for you:

0
Apple - Xcode Help
Help guide and information regarding Xcode (Apple's integrated development environment)
Official
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Apple Store Connect Help - Overview of Publishing an App
Guide to publishing an app on the Apple App Store.
Official
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Apple Store Connect Help - Maximum Build File Sizes
Information about the maximum file sizes for app builds.
Official
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