These were some tutorials that I did with Phaser 3.6. It was fun and I learned a few things but without a game that I want to make, I didn't take it anywhere.
Tutorials:
You make a very simple platformer with the official tutorial
You make a simple platformer and it feels much better than the official one.
You make an infinite jumper game.
A 25 part tutorial to make a platformer. Very cool.
Links:
It's not a very good roadmap as there doesn't seem to be a larger picture. This was something that was probably put it together after someone created the tutorials and videos.
Learning how Tiled and tilemaps work would be very helpful.
https://medium.com/@michaelwesthadley/modular-game-worlds-in-phaser-3-tilemaps-1-958fc7e6bbd6 Some stuff about tilemaps