I'm going to assume you're using linux
It's a program/script, it's called 'neofetch'
Install it via your distribution's package manager (on Ubuntu or Ubuntu-based distributions, "sudo aps install neofetch". On arch/manjaro, "sudo pacman -S neofetch")
Then open your terminal on choice and run 'neofetch'
I don't really know what you mean by music widgets... If you use the KDE Plasma desktop environment, then you can right-click on your desktop and click "add widget" (or something that reads similar), and search for a music widget
Oh, if you mean something similar to the one in the post above you, then you should refer to those as music players. You can search google for a Terminal Music Player and find one that's to your liking. Note that you'll have to download your music locally. (Though there probably are terminal Spotify clients but I've never tried them)