Salesforce Platform Developer II Certifications require you to complete not only the proctor exam, but also those components on Trailhead. Just bear in mind!

Debug and Development Tools consists of 5% of total score in Salesforce Platform Dev II Exam. The topic covers including performance profiling and troubleshooting, and Salesforce deployment tools such as change sets, Force.com Migration Tool, Force.com IDE (retiring), Workbench, Force.com CLI,

Performance consists of 7% of total score in Salesforce Platform Dev II Exam. The topic covers including performance issues, mitigation techniques, best practices, caching, and etc. particularly for Visualforce, Lightning Component, and SOQL and SOSL queries.

Testing consists of 12% of total score in Salesforce Platform Dev II Exam. The topic covers including Unit Testing, testing best practices, testing techniques, testing execution and etc.

Integration consists of topics like web services such as REST API and SOAP API, Metadata API, Streaming API and Analytics API.

This chapter covers a lot of topics such as controller, Visualforce, Lightning component.

Salesforce Platform Developer II exam's largest portion of all: logic and process automation. The topic covers are wide, including process automation, debugging, error handling and exceptions, SOQL and SOSL, Apex, and authentication techniques.

Data Modeling and Management covers topics such as Multi-Language, Multi-Locale, Multe-Currency, compound data types, external objects and ids, custom settings and custom metadata types.

Salesforce Fundamentals consists of 5% of total score in Platform Dev II exam which covers standard system objects, Lightning Platform, Heroku, Fuel and etc.