Please, use something like puush or
ShareX to quickly and easy upload proper screenshots instead of making a photo of your screen, ya goof.
Nice D drive name btw.
So Hammer probably just has a hard time calculating your level. Do you know about optimization? If not read through these helpful articles:
http://www.optimization.interlopers.net/index.php?chapter=func_detail
A badly optimized level will give vvis hell of a time to calculate and may take hours to compleete. Also there appears to be an error at the vvis compile "qhull precision error" now iirc this error can be harmless but when your compile takes ages then this could be the cause of it. The error can be caused be a super flat brush or a gap between brushes that is also very narrow. This is often caused by working with world brushes without snap-to-grid, or perhaps just a too small grid size.
So, if your level isn't optimized, then it's probably the cause. If it is, look for strange brushes, and if you can't find it, and no errors with alt+P you can try using the cordon tool to compiel parts of your map.
My money is on optimization though