Installing ROOT on a mac

I need the data analysis framework ROOT on my mac (macOS mojave 10.14.5) for some coding in c++. After downloading the .dmg from here https://root.cern.ch/content/release-61600 I still get an error when compiling something using stuff from ROOT. I also can't just type in 'root' in the terminal and then use root.

So can someone please tell me how to install ROOT?

I know this is a rather silly question but I'm still a beginner :)

Thank you!