Disabling the widgets panel through the Settings app only removes its icon from the taskbar, but its services keep running in the background. You can execute a command in an elevated Command Prompt ...
To add widgets to your iPad's home screen, you just need to hold your finger on a blank part of the home screen, then tap the plus sign icon.
If you want to get rid of the Dashboard on your Mac running macOS Mojave or earlier, you can do so in System Preferences.