Copy and paste the following into a macOS or Linux/Unix terminal on a system running BASH (highly likely).
git clone https://github.com/spencer-dollahite/clitutor.git;cd clitutor;chmod +x clitutor;./clitutor
Intro tutorial video to come
Labtainers is a free, local, open source lab environment. There are instruction guides and tutorial videos at that link to help you get it set up. It is NOT necessary to get started. The one-liner above will get you up and running quickly and easily. Labtainers is much more involved, but it will offer custom lab environments for better practice without messing up your current system.