I installed Parrot OS 4.7 on Dual Boot with Windows 10 and this happens during booting I tried deleting the partition and reinstalling Parrot OS again but still the same issue! As you can seeThe image describes the issue
Boot into liveusb or livedvd that you used to install parrot OS 4.7.
open terminal and run :
sudo fdisk -l
sudo mount /dev/sda* /mnt
(replace * with the number that shown with type= linux in "fdisk" results)
cd /
cd /boot
ls
cp /boot/initrd.img-*******-parrot1-amd64 /mnt/boot
(replace ***** with numbers that shown with initrd.img in "ls" results)
I hope that was a more detailed tutorial.