Solved Server to test plugins?

I tried the internal IP too, but I still cannot join. What does this mean then? What to do next?
Plus, is it possible to make it that everyone in the world can join?

 

Yes, you have to port forward.

 

If I do that, can everyone in the world join if the server is on?
If not, how can I make it work for all players in the world?

 

Yes. Just make sure to select tcp and the udp protocol.

 

Um, first, I don't know how to port forward, second, I don't want players from the other side of the world to destroy my internet/WiFi/router/etc. if they are hacking. I want to stay safe and not change everything.

 

You can look up your router model at https://portforward.com for a tutorial.

Then use your router's firewall, or just get VPS hosting which comes with all ports already open.

 

But a new server VPS will cost money again...
Plus, I don't know a thing about routers.

 

That's why I said:

 

just http://server.pro