content_entity plugin only works if migrating site within an existing Drupal 8/9 site. If you need to use an external database from a D8/D9 site, you'll need the https://www.drupal.org/project/migrate_drupal_d8 module
Here's an example of migrating files (prior to migrating media items)
As part of the 'Future of UK Treescapes' programme, we have recently launched a site to support the 'Treescapes: Voices of the Future' project treescapes-voices.mmu.ac.uk
Look! No annoying pop-up.
We decided to remove Google Analytics to track user behaviour on this website. Without specific, targeted campaigns, there isn't really the business need for detailed analysis of users on this website. And because we're no longer using 3rd party tools to capture data, we don't need that annoying pop-up for you to opt in to surrendering your personal data.
Google is clearly the market leader for search and browsing, as well as dominating the mobile device market [with Android]. It has its place. But not here. Any more.
A few out of date articles are online on Apache Solr working with Drupal on Lando. Google et al will give you a few close recipes for Drupal 8 but have some errors. The sequence below is tweaked for Drupal 7 - pretty similar approach for Drupal 8, although you can use a newer version of Solr with D8/9.
You need to alter .lando.yml to following:
composer create-project drupal/recommended-projectcomposer require drupal/yearonly