Craft Commerce: Steps Bar in Checkout
The Craft Commerce example template's include a file called meter.html to display the progress bar.

At the top of template there is an array of steps that is used to calculate the percentage as the user progresses through the checkout process.

In order to get your progress bar to show the correct percentage you will need to change the url's for each step to match your site's structure.

Something along the following lines will likely be what you need:

{% set steps = [
  {
    label: "Start Order",
    url: 'shop/test/checkout'
  },
  {
    label: "Address",
    url: 'shop/test/checkout/addresses'
  },
  {
    label: "Shipping",
    url: 'shop/test/checkout/shipping'
  },
  {
    label: "Payment",
    url: 'shop/test/checkout/payment'
  }
] %}


This will then make the following true for the current step and the width will be calculated.

{% if craft.request.requestUri|slice(1) == step.url %}
  {% set width = ((key + 1) * 100 / steps|length) - 20 %}
  {% set class = "sel" %}
  {% set currentStep = key %}
{% endif %}