If you want to unlock new Wung Fu abilities or get better stats in general, you will need to level up fast. To level up fast, we recommend farming side quests, as these will give you a decent chunk of XP.
The same goes for the main quest, which will actually give you probably the most XP in the game. Quests will also give you plenty of chances to earn new gear, loot, and items from rewards and even XP from the bosses and enemies you will fight.
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Defeating both bosses and enemies will also give you decent amounts of XP as well, so you should really focus on quests because of it. But that is not the end of how you can earn XP; in fact, you can earn XP from just exploring and finding new locations in the game.
That being said, farm these activities, and you will level up in no time, and when you do, you will earn what are called upgrade points. These are points that you can use to unlock new Wung Fu abilities in the game. When you earn some, simply visit the Wung Fug tab and choose a new ability from the list to use them.