The Migrate File to Media module provides an easy way to migrate old file fields like images, files, videos, etc, into the media entities with a few drush commands.
So you can have an understanding of how the migration process works, In this tutorial, we will run through a few quick step-by-step instructions on how to migrate specific image field types to image entity reference fields.
Media Module
The core media module is what creates the “media” entity types. If you haven’t set this up yet, or if you are not too familiar with media entity setup, I highly recommend following this tutorial “Drupal 8 Basic Media And Media Browser Setup For Beginners”, before you continue with this tutorial.