In Windows 11, you can choose an app to open each file type individually. Here’s how:
Open the Settings app and tap on the Apps section in the left-hand menu. The Settings app is more hidden than it was in Windows 10. In Windows 11, you need to hunt for a gray gear icon. You can pin the Settings icon to the Start menu in Windows 11, but it's not there by default.
Choose Default apps. Windows 11 lists every single app on your machine. You can search for an app or for the file type you want to assign to an app.
Click on the app you want to set as the default for a file type and you’ll see the list of all file types it’s capable of handling.
Here, Microsoft Photos is set to handle all photo file types, since that program's icons appear next to the file extension entry.
Click on the file type you want to change the default app for. Then, you see a menu like the one below.
The last step is to simply choose an app from the list. (Incidentally, this app selection dialog box is one of the few window types for which Microsoft did not add rounded corners.) After that, you have to repeat the process for each file type that you want to use with that app.
'Open With' Option
Another way to change a default app is to right-click on a file in File Explorer, click Open With (which is more conveniently and consistently the second choice in Windows 11's context menu), and then pick the Choose another app option. Doing so opens up the same app selection box as in the first process, except with a checkbox to "Always use this app to open [extension] files." After that, just check the box and hit OK.