The joy of homebrewing has a section I think called "betterbrew" that is extract recipes plus specialty grains. That's how I started except through the Austin homebrew mini-mash recipes. You basically steep some blend of grains like crystal and carawheat in a strainer bag for awhile and then add the base malt extract after you have removed them.
I'm not sure my beer has gotten any better since going to all grain but there are more opportunities to make mistakes. So I also think about going back.
You can view the whole recipes on the ahb website by finding the click here for instructions link, like this one:
https://austinhomebrew.com/products/ahs-fall-esb-8c-mini-mash-homebrew-ingredient-kit