Category "application.properties"

In java spring, how to best "change secret in production"?

I am currently creating a Java Spring application that works with the spring security JWT. Everywhere I look and read about the "secret string", it says should

Spring Boot Multiple Ports?

How can I have a spring boot web application running on multiple ports? for example 8080 and 80 how can I achive this?application.properties server.port=8080,