Getting started documentation does not explain how to install bundler

[fulldecent]

The getting started documentation at https://bundler.io/guides/getting_started.html is the first step of the documentation https://bundler.io/docs.html.

This first step should explain how to install bundler.

For example I just installed ruby on macOS:

brew install ruby

And now I would like to use bundler. I tried:

bundle

which produced:

/Users/XXXX/.gem/ruby/3.1.0/bin/bundle:25:in `load': cannot load such file -- /opt/homebrew/lib/ruby/gems/3.1.0/gems/bundler-2.1.4/exe/bundle (LoadError) from /Users/XXXX/.gem/ruby/3.1.0/bin/bundle:25:in `<main>'

This issue is NOT CONCERNED WITH FIXING MY PROBLEM. I don't care about that problem right now. This is issue is concerned that the documentation's first step does not bring an interested potential customer from not using bundler to using bundler.