General instructions to set up Ruby and Jekyll on macOS:

brew install rbenv
echo 'eval "$(rbenv init -)"' >> ~/.zshrc
source ~/.zshrc
rbenv install -l
rbenv install 3.3.0
rbenv global 3.3.0
source ~/.zshrc
ruby -v
gem install jekyll bundler

To run locally, open Terminal or Command Prompt in the root of this repo and run the following:

bundle exec jekyll serve --livereload