Hello, your friend has established a career. If you want to apply for other institutions or civil servants (state-owned enterprises), you must first look at the recruitment information released by the recruiting unit. This information will limit the identity and education of recruiters. Your classmate can only sign up for the exam if he meets the recruitment requirements of the recruiting unit. If he doesn't meet the recruitment requirements, people will directly refuse. As for resigning, you can do it at any time.
If your classmate meets the recruitment requirements of the applicant and has passed the examination, written examination, interview and physical examination, whether the original unit can let him go depends on his unit, and we are not sure. Communicate well in advance. If the unit agrees, shifting gears is not a problem.
The cost of resignation is not what we talk about verbally, but based on how the contract between him and his current unit was signed, usually according to the contract.