Magento 2 has two ways to create Database for module:
Install Schema/Upgrade Schema: https://vi-magento.com/tao-bang-trong-magento-voi-setup-script/
It is old and already deprecated in lastest Magento. Now, you should use Declarative Schema to add/modify the table in database for your module
Declarative Schema:
https://devdocs.magento.com/guides/v2.4/extension-dev-guide/declarative-schema/
Exercise:
Create new module, use Declarative Schema to create table with the following schema:
Use Schema Patch to add column: Age, Country to the actor