Disable OneDrive Everywhere in Windows and Apps Completely

Press Win + R keyboard accelerator to open Run dialog box.
Type GPedit.msc and hit Enter or OK to open Local Group Policy Editor.
Navigate to Local Computer Policy -> Computer Configuration -> Administrative Templates -> Windows Components -> OneDrive.
In the right pane, double click on policy named Prevent the usage of OneDrive for file storage.
Select the Enabled radio button.
Disable OneDrive

Click or tap OK when done. //

Uninstall OneDrive

1. Open an administrator command prompt
2. Terminate any process of OneDrive by running the following command:
   taskkill /f /im OneDrive.exe
3. Uninstall OneDrive app by running one of the following command:
   1.1. In 32-bit Windows 10 (x86):
   %SystemRoot%\System32\OneDriveSetup.exe /uninstall
   1.1. In 64-bit Windows 10 (x64):
   %SystemRoot%\SysWOW64\OneDriveSetup.exe /uninstall

One you ran the above command, OneDrive desktop app is uninstalled completely and cleanly. Most of the time, no progress bar nor confirmation dialog is shown. However, when you search for OneDrive, the app no longer be found.