MacOS on Linux VirtualBox
Installation of VirtualBox was straightforward on KDE Neon. I downloaded the Ubuntu version from this website and ran the following command from the downloaded directory.
sudo dpkg -i package-name.deb
Following the instructions by Helmreich Joinery on Youtube made the installation process faster and easier. However, I encountered a few complications after the installation when it failed to boot into the OS. The boot sequence halted at the line displaying a kernel panic followed by system uptime in nanoseconds: some_number. After consulting the comments section, I confirmed that the error was due to an incorrectly set cpuidset parameter within the shell script. The following command modifies the cpuidset parameter when entered in the terminal.
VBoxManage modifyvm Sierra --cpuidset 00000001 000306a9 04100800 7fbae3ff bfebfbff
The image below shows the first successful boot of macOS Sierra from VirtualBox.

Transferring files from host to guest machine
Next came the challenge: transferring files from the host machine (Linux in my case) to the guest machine (macOS Sierra). Initially, after creating a shared folder on the host machine, I attempted to use the standard command for adding a new user on the guest machine: sudo adduser USERNAME vboxsf. This, as expected, did not work, because it was not a Unix command.
After significant trial and error, I discovered this post (https://askubuntu.com/questions/22973/share-folder-with-mac-guest-on-a-linux-ubuntu-host) where a comment indicated that "Guest Additions for Mac doesn't exist". The only solution involved setting up Samba on the host machine and connecting from the guest machine by typing smb://ip_of_host. I later realized that setting up Samba would benefit not only the host machine but also all devices connected to that network.
Logic Pro X on VirtualBox MacOS
I installed Logic Pro X on macOS Sierra, fully aware that VirtualBox would not be able to handle such demanding software.

As I tried to record a standard MIDI track, I started seeing glitches. The playback cursor was not moving at all after the recording began, but the MIDI data was, however, being saved as usual. Working with such software on VBox proved to be very challenging. Unable to record any further, I decided to uninstall the software but keep the OS for some time to familiarize myself with it.