Homebrew is a package manager that "installs the stuff you need that Apple (or your Linux system) didn't." It's very useful for install packages like node, git, wget, yarn, ffmpeg, youtube-dl, etc.
Launch Terminal from Applications > Utilities.
Enter the following command into the Terminal window...
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
Input your administrative user password when prompted.
Press the Return key to continue.
Homebrew will now install. This could take a few minutes.
Homebrew will show you the two commands that need to be run to add the package manager to your path.
Execute these commands in the Terminal window.
You can now search for a package and install a package using Homebrew.
Search for package using "brew search [term]"
Install a package using "brew install [packagename]"
To keep Homebrew updated, run "brew update" periodically in Terminal.