OneDrive will automatically pause when a Windows PC enters battery saver mode, but if you want to stop syncing because you are on a metered or slow internet connection, you can Pause and Resume your sync.
Pausing and Resuming can also help if OneDrive status displays “Processing changes” for a long time.
How to Pause Syncing
To Resume Syncing
Syncing will resume automatically after the Pause time has finished, or you can manually Resume syncing at any time.