Can you hack into the PC via a Minecraft Craftbukkit server?

I have a Minecraft server and I gave a few people the Ipv4 address that I previously edited with https://www.noip.com/.

Is it possible to hack my PC via the address and if so how can I do something about it, because I have a friend whose older brother taught him how to hack.

My friend says that he managed to hack my Pc via this address and I don't know if it's true and since I find it very uncomfortable that he could control my Pc all the time.

I know he programmed a Minecraft Ki that felt like 1000 hacks on my server, my security system didn't do anything.

I don't think a Minecraft programmer can hack your computer. That would be a very complicated thing and for that you would have to download any program he created. So, as long as you don't download anything from him, everything should be fine, so no need to worry.

Thank you very much