(use-package dashboard
:ensure t
:config
(dashboard-setup-startup-hook))
To replace the startup screen with a list of recent files, bookmarks, and Projectile projects you've recently visited.
Remember, though, that just like this document describes, a big part of Emacs is not running it repeatedly, but rather starting it just once and keeping it alive basically forever; you're only rarely going to see the startup screen if you're doing orthodox Emacs.
In the sense that use-package should pretty clearly be bundled with Emacs by now, sure. You don't need Projectile installed to use dashboard (I barely use Projectile, and have it turned off in my dashboard thingy).
Remember, though, that just like this document describes, a big part of Emacs is not running it repeatedly, but rather starting it just once and keeping it alive basically forever; you're only rarely going to see the startup screen if you're doing orthodox Emacs.