Hello,
I like how is this theme showing post page. Those cards with post are cool,
But I want to know:
Is it possible to have more post pages than one? Like if I can add that post list to any page like some widget and also if I can choose from my post categories whitch posts to display at post page.
It is not possible to create multiple post pages but you can use category pages like this and that way you will answer all your questions. Here is an example for category page: https://colorlib.com/sparkling/category/featured/
These category pages can be added inside menu and they will look like different blog pages.
If this doesn’t help, you will have to look for some plugins that helps to filter blog pages. I haven’t used any, so I can’t provide you any recommendations but I know that there are some available.