By default windows os has various background services enabled that consumes datapack to stop it do the following:
Disable windows update
Open RUN Type services.msc and select the Windowsupdate services and disable it
Set metered connection
Open your wifi setting and check āMetered conncetionā for connected wifi
Other things to do
- turn off background apps
- turn off live tiles
- turn off pc sync
- turn off updates from settings app
- turn off startup apps