Huawei Mate 20 Pro
Turning data roaming on or off
You can limit your data usage when abroad by turning off data roaming. You'll then not be able to access the internet using the mobile network when abroad. You can still use Wi-Fi even though data roaming is turned off.
Press Settings.
Press Wireless & networks.
Press Mobile network.
Press the indicator next to "Data roaming" to turn the function on or off.
If you turn on the function, press OK.
Press the Home key to return to the home screen.