Accessing the client config files
To find the config files, first press your windows key + r. This will open the run menu.

Enter in “%localappdata%” this will take you to your local appdata directory,

Next, you’re going to want to go to this directory from where you are “AppData\Local\OPP\Saved\Config\WindowsClient”

You are now inside the config files directory, the file you will be editing is Game.ini

Editing the Config file
Now that you are inside game.ini, you need to enter in these lines.

[/script/opp.rbsettings_gameplay]
DefaultFOV=110.000000
AimingFOV=110.000000

The number value is your desired FOV, by default it is 90.0.

Once changed, save the file and load up the game, you will now see your new field of view.