Hi! I can't explain how long did i wait for this! This is another cool metroidvania by you! But it's not "another" because this one is much more confusing lol.. I got lost... i enabled fans and portals, i think i tried to get everywhere, but i can't find where i can go.
If you have fans and portals enabled, you should be able to find a stronger sword and then, with that, double jump boots, and then you should be able to find the four magic gems that will unlock the door to the final level.
Yes, I agree that this game can be very confusing. It's surprisingly hard to make a metroidvania that feels intuitive in the sense that the player always has an idea where to go next (I think this is also true for many commercial metroidvanias, I have stopped playing so many of them because I have got completely stuck!)
There is a locked door on the top-right corner of the map. There is a huge tree leading there. This door will lead you to the sword eventually. And to find the key that unlocks the door, you need to find running shoes and then go to the caves near the place where you found the magic book.
(Now that I write these things down, I sure realize how confusing this game can be. Sorry about that, I try to remember this next time I make a game!)
If you need further help, here's a map of the "outside part", where I have circled the places where you should go and in which order.
(in hindsight I should have made the game's internal map more useful, but I started implementing it a bit too late and it was hard to put any meaningful info there in that point)