Htop is super easy to use
Linux top is very useful in seeing system processes. The only problem is the general layout and commands are not obvious while its open. For those reasons, I like htop (htop – interactive process viewer). It lists many options on the bottom of the screen and you can press the letter h to get more detailed information. Once in the application, you can press f5 to activate tree view or you can press the period key to change the sorting column. I also use the f4 key a lot to activate the search functionality. HTop is definitely a must-have application
In a Debian based Linux distro like Ubuntu, Gnome, Kubuntu and plenty more just run this comment below which will install it because htop is not installed by default.
sudo apt install htop -y;
Some resources: