Edit a newsletter template - wordpress-! -- 2 - 15/01/2018 16:12 EST

Hello. I am using the plugin Newsletter at my wordpress website. We have there a custom template which i want to add a feature. I want to have one article, that i will select it to be on the top of the newsletter so its going to be something like this, in the red rectangle ( [login to view URL]) in the center a bit bigger than it is the others i want to have the ability to choose which exactly post it should go there. And when choosing this, not to be in the rest posts that follow underneath