Storage settings on iOS crashes while calculating
Most of the iOS crashes like this are corruption from data and not reproducable. If you power down the device while it’s in airplane mode - no data connection and power up, try again.
If you can reproduce this crash, you can be sure it’s the data on the device that you can control at that point. Check a backup and/or delete any and all apps and data you don’t need. At some point, you’ll need to restore the os on the device or manage storage via USB / cable / iTunes.