You need a stable internet connection and a device with a microphone and camera. You can use a computer, tablet or smartphone. We recommend the use of a computer and a pair of headsets to assure the best possible sound quality. The recommended download/upload speed requirements for Skype video call is 300kbps / 300kbps. You can check the speed of your connection here.
If you are not a fan of Skype, you can use alternatives like FaceTime, Google Hangouts, Zoom, Messenger... Agree with your teacher on which technology and/or application suits you both.