How can i use objects of models of Magento for save my form data of my custom module

[emanmohameda68]

I want to save a new record in (customer_entity) table and (inventory_source_item) table any guide for code standard dealing with Magento models and assigning form data to a specific field 

how can I apply the functionality of CRUD on these tables (customer_entity) table and (inventory_source_item) table in my custom module