Hey! Dont worry 
Here’s ur solution
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For interactive menu its called tappable overlays menu…For that u need overlays and background
U can request in shops for overlays or u can make a separate thread to request
And for coding that
Pls read this thread
A Basic Guide to Tappable Overlays -
For that u need to learn spot directing and use it in moving ur characters all the time
U can take help from these threads
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To make ur own u need to learn editing with the software u are available with and to upload ur own overlays and background
U can take help from here
How to upload your own background and overlay -
There are 2 main types of cover
Edited and Drawn
In under Art Resources category u will find many art shops from which u can request for both edited and drawn covers…
I myself have a shop if u are interested
Bloom's Free Art Shop 🥰 [Closed till March 2022]
If u want high realistic art there are many commission artists who take payment to make arts for u story
And if u want to make urs then also u hv to develop some editing skills 
I hope this helps
If u have any queries with anything feel free to pm me with more questions I would be happy to answer 