ENTRA ID - Licenses and Features

Licenses
FREE
Provides user and group management, on prem directory synchronization and cloud resources, basic reports, self-service password change for cloud users, and SSO across Azure, MS 365, and other SaaS applications.
P1 - Everything in Free plus:
Hybrid user access both on-prem and cloud resources, advanced administration such as dynamic groups, self-service group management, MS Identity Manager, and Cloud-write back capabilities.
P2 - Everything in P1 plus:
ENTRA ID Protection for risk-based conditional access to apps, company data, and Privileged Identity Management. PIM allows for discovering, restricting, and monitoring administrators and their access to resources - "just in time" access when needed.
Pay as You Go 
Self-Explanatory. Pay for features and services with various factors being used to determine cost.