What to make , and how to make

I want to participate in this challenge , it's my first time of attempt , so I don't know what to do in it , I mean on MacOS/iOS/iPadOS , what I have to create , a app , or playgrounds ?

And what kind of things I can create , games , productive app ?

Kindly tell me all the things broadly about this .

What to make , and how to make
 
 
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