New to emulators need help!

so im trying to play pokemon pearl on NO$GBA everything is working but in the very beginning the professor asked me to press the middle button on the pokeball but no button works

Come on guys i really need help XD

You don't have to bump your topic,we'll reply eventually.
Okay?
You should try playing Pokemon pearl on DeSmuMe.No$Gba is known to have issues with Pokemon games.
Download DeSmuMe from:
http://www.desmume.org
You won't have any issues while playing on DeSmuMe but it can get slow.

It's nice to see some people still understand how to produce a quality post!