Need suggestions/advice on upgrading a Drupal 6 site to Drupal 8

Just joined I could use some advice/suggestions. Here’s my story…

My wife has a Drupal 6 website that I built for her back in 2011. She has used it consistently over the years since then, but Drupal was never updated. I came down with serious health problems that made that out of the question, and she had neither the time nor skills to do it herself.

Recently we found out that her site is no longer running. I spoke to the tech support group at her host and they told me this is due to the fact that they recently updated php to php 7, and Drupal 6 will not run on php 7.

So… I need to upgrade her site to Drupal 8. My health has improved and I have the time to do this now. But…

I have a few issues:
– My memory for all things Drupal is almost nil. Too much heavy duty water under the bridge.
– Her site cannot be accessed online.

I have downloaded the entire site to my local machine and have installed XAMPP as well, with both php 5 & 7 available to me.

What steps do I need to take to…
1) get her Drupal 6 site running locally
and then
2) upgrade that site to Drupal 8

I very much appreciate any suggestions, pointers, ideas, links to articles/posts/resources. I do have general technical expertise, but my knowledge of the inner workings Drupal at this point is hazy, if not entirely non-existent.

Thank you.

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