Explanation/Reference:
The CREATE FULLTEXT INDEX ON table_name command creates a full-text index on a table or indexed view in a database in SQL Server.
Example: The following example creates a full-text catalog, production_catalog, in the AdventureWorks sample database. The example then creates a full-text index that uses this new catalog.
CREATE FULLTEXT CATALOG production_catalog;
GO
CREATE FULLTEXT INDEX ON Production.ProductReview
..
References: https://docs.microsoft.com/en-us/sql/t-sql/statements/create-fulltext-index-transact-sql