If you regret the choice you made when choosing professions in Stardew Valley, you don't need to worry. Stardew Valley doesn't lock you into a choice. You can change your profession anytime by using the Shrine of Uncertainty.
Where to find the Statue of Uncertainty in Stardew Valley
In the sewers of Pelican Town is a strange, round statue known as the Statue of Uncertainty. It's right at the entrance of the sewers, and you can interact with the statue as soon as you find it. In exchange for 10,000g, you may choose to change any of your unlocked professions. Your professions come from Farming, Foraging, Fishing, Mining, and Combat. Select the one you'd like to change, and once you go to sleep, you'll be asked to choose a new profession.
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You will also have to select your Level 10 Profession if you have unlocked a second one through reaching Level 10. It is possible to switch between Professions every day, but you'll need 10,000g every time.
How to unlock the Sewer in Stardew Valley
While it's time-consuming, unlocking the sewers is a simple process. Gunther gives you the Rusty Key after you donate 60 items to the Museum. Use the Rusty Key to unlock the entrance to the Sewers.