You can change your account's country in the Settings menu. To access it, you will have to tap on the tool icon you will find on the top right-hand corner of the home screen.
Once you enter, you will find the name and flag of the country you have previously selected. If you press it, a menu will appear where you will be able to choose the country of your preference.
Keep in mind that the game will take your region into consideration when assigning you questions.
We invite you to visit the article: Why do I see questions specific to other countries?