A metered connection is an Internet connection that has a data limit associated with it. Cellular data connections are set as metered by default. Wi-Fi and Ethernet network connections can be set to metered but aren't by default. Some apps might work differently on a metered connection to help reduce your data usage. Also, some updates for Windows won't be installed automatically.
Note: If your device is running Windows 10 (version 1903 or version 2004) and you turned off the Set as metered connection option for your cellular data connection, your device might reset to metered again when it wakes up from hibernation, or after it shuts down.
To set a Wi-Fi network connection as metered:
Select Start > Settings > Network & Internet > Wi-Fi > Manage known networks.
Select the Wi-Fi network > Properties > turn on Set as metered connection.