This is very simple to change your computer default language . You can do both on MC and Windows. The default language will never  change your internet browser language. Press Window button on your keyboard,. You can also see a Setting Button on the top right corner of your laptop. Go to “Time and Language setting”option. Open Search tool and search your desired setting there, then you will see a new option “Region & language”. There is another option “Add a Language”, select it and save. But you will see different regional dialects available there. So, click a dialect to select it.By doing so, click on your Added language, and then open “OPTIONS” and download language packs. Now click on Back option. Click the Language again and click set as default.