Entitlement Process - Chirag-ahir/SFC-Preparation GitHub Wiki

An entitlement is a record that represents a customer's right to receive support or service based on the terms of a contract or agreement. You need to enable entitlement from setup in order to use it.

Milestone defines a specific action or task that must be completed by the support team within a defined timeframe

The entitlement object is a junction object between Entitlement Process and Case.

E2E Guide: https://www.salesforceben.com/complete-guide-to-salesforce-entitlements-and-milestones-in-service-cloud/