Linux is an operating system, like macOS or Windows. It is also the most popular Open Source and free, as in freedom, operating system. Let's get started with Linux...
1. You can directly install Linux OS in your systems as it is best in practise and to learn a CLI based OS, instead the GUI of Linux OS is also fun to go with support most of the applications and files as Windows OS do could be entertainment file, Packaged files etc..
2. Or we can launch an Amazon Machine Linux AMI instamce(EC2) using AWS Cloud services, by just creating an account on AWS using a free-tier subscription for all the services for a year with some limited usage hours.