In Photoshop CC Preferences:
Interface > Text > UI Language > English
If English is not available, you must download it using your CC Desktop app and choosing English as the language. The app list should show an Install option for Photoshop. This example is for German, but same idea. You get to CC Preferences by clicking on the gear icon in the screenshot below.
After you install it, English should be seen in the UI Language menu. Select it and restart Photoshop.