Error connecting to IP on my locally hosted Minecraft server?

There's always a mistake when a friend of mine wants to go to the server. (Picture in the attachment) I think I have to do a port forwarding can help me because one please. Or what else could it be? Please help me

Are you both in the same Wi-Fi network?
Did you run a server on your computer or did you press "Open World on LAN"?

It seems like the server has been closed. ("An existing connection was closed by the remote host." - I would recommend that you use Hamachi for a private server.) If you want to have a friend joined, just click on "Open in LAN" and your friend's IP Then, you should make sure that both of you use the same Minecraft version, as shown on Hamachi, as well as the number that should be in Minecraft Chat.

I bought a Nitrado server so no matter but thank you anyway

I bought a Nitrado server so no matter but thank you anyway