Hi Ameer:
Good day!
For the CAPM exam, don’t worry about anything that is outside of the PMBOK guide. Anything outside of the PMBOK guide shouldn’t be tested in the CAPM exam.
Configuration means specifications. For example the configuration of a laptop can be a 15-inch HD screen, DVD drive, 8GB memory, 1TB hard drive, i7 processor etc. Configuration management means ensuring that the project delivers a product or service with the agreed/required specifications or configuration. Any change in the agreed configuration can only be incorporated once proper change control procedures have been followed. The configuration management plan and the change control plan, both are components of the project management plan.
Please let me know if this resolves your confusion.
Warm regards,
Khurram