Beginner question about modifying the default loop

Starting a new project with Sage 9 and I’m having hard time trying to wrap my mind around Blade. This seems like a total beginner question, but how do I go about separating the first post in the default loop? I’m trying to create just a simple helper function in my controller, but even that seems weird and unwieldy. I can do it by setting a variable directly with PHP on the template, but this seems wrong.

@php($first = true)
@while (have_posts()) @php(the_post())
  @if ($first)
    @include ('partials.content-featured')
    @php($first = false)
    @include ('partials.content')

What I would like to do, is to maybe use $wp_query->current_post and add other conditionals like is_paged to the mix. How would I go about doing this? I don’t want to constantly fall back on using PHP in templates.