Can you always switch a port on and off at the fritz box?

Hi, I have set up a private minecraft server and only have to activate the port on the fritz box. But I wonder if I can switch the port on and off automatically or how does it work?

What does "automatic" mean? According to which requirements should the port be blocked or released?

With most routers, the release is permanently valid, but you can change it manually at any time. Some routers allow you to store rules, such as A schedule.