can i should click start playback first?
Make sure you have downloaded all the dependencies, like you see in this picture.
When you open the scene, you will have some options to choose from.
Embody Mode and Possession Mode are for virtual reality. Desktop Mode is for non-VR. Clicking on one will set up the scene for you.
After that, you can control the scene with the user interface.
Part 1, Part 2, and Part 3 will begin the animations.
If you want to change the girl's appearance, select her and load an appearance preset. Then click "Load Clothing & Physics" to automatically adjust her for the scene.
(If you are having troubles reading the user interface in English, I recommend using the Google Translate app on your phone, and point it at the screen. It will translate the text for you.)
I hope this helps!