Comment by mdaniel

Welcome to the journey!

If you haven't seen it yet, lichess.org has a bunch of fun content

https://lichess.org/practice

https://lichess.org/training (it's labeled "Puzzles" in the UI; there's a difficulty picker hidden in the bottom left of the page)

They have mobile apps, too, although regrettably not all content is available on the app for some horrible reason