Boot Camp is a feature of macOS that lets you start up your Mac in Windows. If you have already installed Windows on your Mac using Boot Camp, you can set Parallels Desktop to work with Boot Camp using either of these two options:
Note: this feature is not available in Parallels Desktop for App Store. For more information on the differences between the Standard and App Store editions, follow this link.
Set Parallels Desktop to run Windows from the Boot Camp partition: Changes you make in Windows applications either while working in macOS or when you start up your Mac in Windows using Boot Camp will be reflected in both places.
Windows running from Boot Camp has the following limitations:
It can't be paused
It can't be saved as a snapshot
It can't be compressed
Import Windows and your data from Boot Camp into Parallels Desktop: Windows running from Parallels Desktop doesn't have the above-listed limitations. Boot Camp and Parallels Desktop are separate. Changes you make in Windows applications while working in macOS are not reflected when you start up your Mac in Windows using Boot Camp. When you import Windows from Boot Camp, Parallels Desktop creates a .hdd file and copies all the contents from Boot Camp to it. This operation will not affect the existing Windows on Boot Camp setup. All you need is just enough free disk space on the Mac's hard drive.
Open Parallels Desktop (in the Applications folder) and choose File > New.
Click Boot Camp, and then follow the onscreen instructions.
Note: If you plan to start up in Windows using Boot Camp, it is recommended that you shut down Windows in Parallels Desktop rather than suspending Windows.
Set Parallels Desktop to use Boot Camp, as described in the steps above.
Right-click (Control-click) the Boot Camp version of Windows in the Control Center and choose Import Boot Camp.
Click Import.
Locate where you want to store Windows and your data, and then click Choose. Windows and all your data will be imported from the Boot Camp partition. You can still use the original Boot Camp Windows installation, separately from Parallels Desktop.
Important: The first time you start Windows after setting Parallels Desktop to work with Boot Camp, Parallels Tools are installed to allow seamless operation between Windows and macOS. Once Parallels Tools are installed, you're prompted to restart Windows.
You can save disk space on your Mac by importing Windows from Boot Camp into Parallels Desktop and then deleting the Boot Camp partition. Here is how it works:
For example, you have a 40 GB Boot Camp partition, and only 20 GB is occupied by Windows and its files. The other 20 GB is not used.
You choose to import Boot Camp. Parallels Desktop copies Windows and all its files from Boot Camp into a new virtual machine. This virtual machine will occupy only 20 GB of disk space.
Once the import is complete, delete the Boot Camp partition and save 20 GB of disk space.
Note: The hard disk of the resulting virtual machine is not limited to 20 GB. It is expanding, which means that you can continue installing applications and downloading movies, music, etc. The disk will grow in size proportionally. For example, if you download a 5 GB movie to this virtual machine, it will occupy 25 GB of disk space.