The world is fairly open ended and you can complete the first 3 dungeons in any order you wish.

Some enemies were nerfed to compensate for a dungeon potentially being your first, so difficulty wise it's relatively tame up until the final dungeon. There's plenty of handy optional items to find throughout the world though, and doing so will make things a pretty easy romp.

Link has stumbled upon a land cursed by an evil fairy. Monsters are a running around everywhere, and villagers are even being turned to stone. He'll have to find his way into this fairy's domain and stop them before things get worse!

Extra Items:
12 Heart Pieces
8 Magic Containers

If you collected the above, by the end game you should have a total of 9 heart containers and 9 magic containers.

Of course, there's also a load of optional items scattered throughout the overworld in addition to the above.

General Tips:
The lens of truth can be found somewhere around the center of the main overworld map. It's by no means required but it might help with finding a particular secret item or two.

Looking for potions? You can find the letter in a cave far south of the town. To actually buy potions you'll need to push something heavy...

You might notice there's a gauntlet dungeon "shop" in town. If you want a better sword you should complete it before entering the final dungeon. Then again, you might find a good substitute for the sword if you're looking hard enough.

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