Okay. So I will explain you how Dynamic components work.
When we use for each number block, we use Create Dynamic Component block inside for each number block so that the particular component will be created for a certain length of list.
Coming to Dynamic components ID, particularly we use get number block to set the id for Dynamic Component so that the ID will not repeat itself, or else, we will get error.
For design parts:
We can literally create anything using Dynamic Components extension. I will recommend you to create a static layout, i.e. a layout which will have everything that you want inside Dynamic layout. After creating a static layout, try creating the same layout using Dynamic Components. As you are a beginner, drag and drop all the components which you will be needing inside your layout and make all those components invisible, so that you will not have any problem while creating it.
To know how to create custom layouts, you can check out this guide:
If you still have any confusion, feel free to ask. 
Hope it helps.