Drupal 8 provides an easy solution to this by providing built-in features for migration. Let's take a look at how. I will try and elaborate as much as possible so that this article can become your full guide to migrating content in Drupal 8.
Before we get into the how, let me create a glossary of some terms that I will use throughout.
Migration API is the key to move content from any source to Drupal 8. Migrations are basically ETL processes. ETL is the abbreviation for Extract, Transform Load processes.