There are a few options to do that:
- If you are using Edge or Internet Explorer, the language of your system will be used to display the portal. If you want to change the language of the portal to English, change the default language in the computer's Settings app
- If you are using Chrome, the language can be changed by going to chrome://settings/languages; there you can add English (if not there already), and move it to the top
- You can override the language by using the ?l (lowercase L) parameter: if you browse to https://web.powerapps.com?l=en-US you will get the page in English, regardless of the system (or browser) configuration
