DDL and SQL are
text. Images are usually not helpful. To preserve text formatting here, use BBCode code tags.
Re lists, we don't get to make up how a relational database works. Before we work with one, we need to familiarise ourselves with how they work, eg with a summary like
https://www.artfulsoftware.com/mysqlbook/sampler/mysqled1ch01.pdf.
A fundamental premiss of relational databases is
atomicity, one value per cell. A value is atomic if it will always be inserted and retrieved as all of itself. Relational databases depend upon this premiss. A list isn't atomic. So yes, lists in single cells are bad practice.
Is queryable text an exception to the rule of atomicity? No, a text or blob field is stored & retrieved as a unit.
Is a JSON column an exception? It's more a fudge. It does support lists, and as a fudge it pays the price---JSON queries in RDBMSs tend to perform poorly.