My download stalls at a certain percentage or stays at Download Starting/Stopping
Try launching the stalled game by double clicking it. This may allow the download to finish.
If the issue persists, please double check your current download region:
The issue is usually from a router interfering with the download process. Please unplug your router and connect your computer directly to your internet connection to test the issue. If this corrects the issue, please resolve the router issue using this guide: Troubleshooting Network Connectivity
Make sure your Internet Connection setting is correct for your current connection:
In the Steam application, Click Steam > Settings > Downloads tab and make sure the speed is correct, as incorrect settings may affect your Steam downloads.
You can also try clearing your download cache.
Or the issue could be due to another program interfering with Steam. Please complete these guides to further test the issue: