Use Gem "wicked_pdf" or any other which you like. Create an Avo action button to generate a PDF file. Create an action in the controller and link this to your AVO-generated button. Create an HTML template file and pass the below @users in this file. In your action, do your logic something like this.

def your_action
  @users = User.all
  respond_to do |format|
    format.html
    format.pdf do
      render pdf:         "PDF file title",
              page_size:   'A4',
              formats:     [:html],
              template:    'your_template_file_path',
              layout:      false,
              zoom:        1,
              dpi:         400,
              disposition: 'attachment'
    end
  end
end

That's all you need to do.