Unity - Together with VRoid - Your Own Character Appears in Your Room! [v2024.06.26] [VR game shop]

There's just nothing you can do here.
The game itself does not really come with any models/girls themselves except the tutorial one. The dev just expect you to make one or visit their website. Even if you make an account on their website, most models aren't even available to download anyway, and even if they are, most of the functions are not available.
It baffles me how much developers expect from your ordinary user who just got the "game."

The controls are awkward at first, but the customizability with Vroid makes it more than worth it. VRM models converted from other files will not always work with this game, despite working well model viewers or editors.