Once they are satisfied that you meet the minimum qualifications/requirements for the job, you get some time to prepare before the interview (you also have to send them a passport sized photo). Before the interview, they send you some materials to prepare for the classroom demonstration that you need to do. They also give you the opportunity to book into an online video session where you can get some hints on how to prepare for the interview. They like you to be very positive, upbeat, use videos, props (eg hand puppets), decorate the wall/background behind you with educational and bright materials.
You will need to practice being able to teach your lesson on camera within a short timeframe, eg practice how long it takes you to talk about what you can see on screen before moving onto the next screen
Although you will be using Zoom for the interview, this won't be the software you will use when you start the job. You need to practice using the tools on Zoom, so you can speak to the camera and annotate your work on screen at the same time. For example, you will need to use the drawing tools to draw circles around or underline words on the screen.
The interview will begin with a few short questions about your experience of working with children, before moving onto the classroom demonstration. You will be given feedback immediately after your interview, where they will tell you if you have passed or failed. If they think you have potential but just need to improve some things ,they may invite you to a second interview. They are very fair in this respect, as they know the online classroom demonstration isn't easy, as it's a diferent environment to teaching in person