Change default programs in Windows 10
On the Start menu, select Settings > Apps > Default apps.
Select which default you want to set, and then choose the app. You can also get new apps in Microsoft Store. Apps need to be installed before you can set them as the default.
You may want your .pdf files, or email, or music to automatically open using an app other than the one provided by Microsoft. To choose default apps by file type. scroll down and select Choose default apps by file type.
Change the Default by Using Open With in File Explorer
(Using PDF docs as an example)
Open File Explorer and navigate to a folder containing your PDF file. Right-click on a file and choose “Open with > Choose another app”.
A pop-up will appear that will let you choose a program for just one time. Or you can also select the “Always use this app” link to make it permanent. From this window, choose the default PDF reader of your choice.
If the default app is not listed in this window, then you can select a different program located in your PC. Click “More apps”, select an app or scroll down to see “Look for another app in this PC” link. Click this link to browse to the program that you want to set as the default PDF reader, and choose the “Open” button to set it as the default.