To enable USB debugging in the Android operating system, you need to open “Settings” – “Developer options” and tick “USB Debugging“.
If this menu is not available in the settings, you need to open “Settings” – “About Phone” and tap (touch) the item “Build number“, then the “Developer Options” item should appear in the settings.
USB debugging mode allows you to work with the device using the ADB utility, install and uninstall programs via ADB, view debug messages, be able to get root rights (full access to the operating system), etc.