Someone wanted to learn this too, so Grasp built them a personal learning path.
You can keep exploring this one or create a path like this one shaped around you.
Recommended resources
Module 2
Introduction to Declarative Pipelines
Module 3
Secure Credential Management
Module 4
Advanced Pipeline Control Flow
Module 5
Automating Builds with Triggers
Module 6
Distributed Builds with Jenkins Agents
Module 7
Docker Integration in CI/CD Pipelines
Module 8
Artifacts, Testing, and Notifications
Module 9
Multi-Branch Pipelines and Git Workflows
Module 10
Reusable Pipelines with Shared Libraries
Module 11
End-to-End CI/CD Project
Module 12