There will be an automated voice that will answer your call. When you hear this voice that means that your speakers are good. Then you will be asked to record a message which will be played back to you, to check if your microphone is working.
2. To check your video calling feature, add and video call user bill-on-skype-video-echo. This is a free and independent video testing service, not affiliated with Skype or with this blog (you can just delete this contact once you confirm your video calling option is working).