#Installing OS Dual boot:

# Download OS from official website [All operating systems are free to download from their official website]

# Make Bootable pen-drive

*Download etcher and select downloaded ios image, pen-drive and select burn.
!!This will delete contents in pen-drive.

# Change partition table of Hard_drive/SSD to GPT [optional]

# why GPT over MBR?

      * MBR partition limits number of primary partitions to 4 while GPT doesnot
      * We cah use any size of storage in GPT (M** Limits to 2 TB)
   (This was easy in my case with Gparted in parrot os rom bootable pen-drive)
   (There are simple ways to do that even without deleting data from drive)

# Enable UEFI boot from BIOS [press F2 immidiately after turning computer on, search and check UEFI boot] (optional)

     * GPT requires UEFI
     * UEFI is more secure than Legacy boot method

[Changing partition to GPT and selecting UEFI actually solved os not found in grub problem]

# Install:

* Unmount the space OS to be installed in
* Boot through bootable pen-drive and install.(F2 after powering on computer)

Hello