This game is pretty cool!
The tutorial was a good idea, even with it there I still had some confusion but I figured it out for the most part. You have an interesting concept of travelling to different worlds and gathering resources, that idea has lots of potential already. The mining aspects reminded me of Minecraft, and then I realized that you can't craft in this game... Not necessarily a bad thing. This would be an excellent multiplayer, I'm picturing epic boss fights and raids!
I think you should expand on the materials, the worlds, and the inhabitants of those worlds. Put in some unique enemies that have traits linked to their native world; Maybe they're weaker or stronger to certain materials from other worlds?
The default walking and jumping speed is a little slow for my taste, in terms of playability. There doesn't seem like too much to do right off the bat except mining resources, unless I'm missing something. Put in something cool right at the start that can hook players... like maybe a special scene if you mine something specific, or a secret dungeon you can reach by digging a hole in a specific pattern.
Feel free to check out my game: https://wasabiiii.itch.io/grass-elemental-demo-demo
Get creative, sky's the limit!