Design a overall design guidelines for an app

I need a good designer who can help me come up with an overall design for my app, it’s a crypto app . Not sure to go with light or dark mode or a mixture of them. I want the users think they can trust this app and have a great design experience from it. Stability and trust they should think when on my app. I just need s great design , so you only have to show this for the attached screenshot .
So do your own designs for this app in one screen