If you are talking about the Android P beta then
Go to this Nokia developer link
I would advise not to update to the Android P beta as Nokia 7 Plus should receive the Android P stable version once it's released on August....for the Google pixel...... maybe at the same time Time or few months later.....
Beta versions are very unstable....(Nokia 7 Plus beta is not stable as the Google PIXEL beta)
If you are not a developer please don't upgrade to a beta version as can cause problems
If you are taking about the Android P beta......
Then just search for "Android P beta" on Google
You will get the "Android P beta devices" page.......click on it
Then find Nokia 7 Plus on the Page and click on
"GET THE BETA" Link
You will be then directed to the Nokia Android P beta page then follow the instructions
I would advise you to not to upgrade to a beta version of Android P as it's very unstable and can cause problems if you are not a developer don't try it
Also The beta update cannot be installed via OTA
The status stable version will be available as an OTA update
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