Since Windows 8, the shutdown is a logoff of the user + hibernation of the kernel/Windows services.
So booting is now a resume of the kernel/all drivers/services + login of a user. This resuming of services/drivers is much faster compared to a full boot where Windows has to start each service/driver again. So everything is fine. Si vous voulez the old boot/shutdown or dualboot with Linux systems, disable fast Startup.
Otherwise you can't mount the Windows partition in Linux.