How to Change Default PDF application
Use the below steps to change your default applications so they open automatically with your chosen application (e.g. Changing PDF to Nitro or Adobe)
Step 1:
Search for "Default Apps" in your Start menu
Step 2:
Select "Choose Default apps by file type"
Step 3:
Scroll down around 3/4 of the way down and find ".PDF"
Step 4:
Select the application Tile and change your default settings to your desired software