Storyboard from concept

I have a concept that my graphic designer made.

Great.

What are the objects you identify out of this design ?

-> Do you have different scenes that will each be a separate ViewController. That is essential, because that will define the logic of your app

-> Have you defined how you transition from one scene to the other ?

-> Which are just images for display ?

You need to split it in different images that will each display in a UIImageView

Has your designer provided a png or jpg file for each ?

-> Which to turn into button because user should action them ?

-> which are areas for text entry ?

-> Which are tables or collection displays

-> etc

Only you, as app designer, can do this analysis, and it is essential to do it.

I'm a bit stuck on how to add this to my storyboard.

Once you have done this, including in storyboard is straightforward.

It's a great UI but I don't know how to make it a reality!

We have to believe you, but maybe, maybe not. Are you speaking on graphical look or user experience ?

Anyway, without seeing anything to understand what you want to include in your app, it is very hard to be specific.

Don't confuse Xcode 'Storyboards' with traditional storyboarding/prototyping.

As Apple says "Storyboarding allows you to graphically arrange all your views within a single design canvas, where you can then define the app's logical flow, and even assign transition animations."

Keywords 'views' and 'flow'. It's up to you to translate your graphically represented UI into the appropriate mechanicals...views & segues (transistions).

I think the more common term for where you're at (idea-to-Xcode), is prototyping - see h ttps://www.smashingmagazine.com/2017/11/designing-app-idea-sketch-xcode/

Have you seen: https://developer.apple.com/xcode/interface-builder/...?

Finally, don't forget the Human Interface Guidelines for encouragment.