hello would you please advise anyone to set Ruby on rails in netbiens?

Just download the one that has it included already, pick the one that
has "Ruby":

I have downloaded it. But if i write a project, and I want to try it
so I will not show my result. But there is just a warning about the
error, i tried to program a web page and there was an error message,
I have installed on my computer apache too, it may be that?
Thank you in advance for any advice

You right click on the project and choose "run" to start a server.
The default is webrick but it will run mongrel if you have it
installed. When it runs (it takes a few seconds to start) it will
open your browser to http://localhost:3000/.

thank you for the advice, it works