What is the application process like for TNB?

No need interview, you're automatically embarked after you sent in your application. Can get close-to-home placement if they are opening for your course.

No claims for mileage, even you have to travel alone far. Environment depends on your boss'. If you're privileged enough, look for another job first before accepting the Protege position at TNB. They will not rotate you across departments. And depending on the department, might not give as much as exposure as you expected. They don't care about proteges.