How to programmatically generate tables, models and relationships between them in laravel?

Question

Laravel

For example, there is a regular online store, the Category and Product model (Categories, Products tables)
In Product - products are stored in Category are categories. Communication is admissible 1-1.
You need to make it possible to programmatically add more directories.
There is a lot of data, more than 500,000 products in each catalog. and for example, there is a directory "Building materials" and you need to add a directory "Household appliances" - each directory should have a table Categories, Products.
The bottom line is not to store all the data in one table, there are a lot of them. How is this done correctly?
How then through api to access models and use normal eloquent to work with tables?

Answer 1

https://laravel.com/docs/5.7/eloquent-relationships