If you already have a 3D model to use as a 3D view, you can load it instead of creating one from scratch.

Select Render Walk → 3D View from the side menu.

Click on “Use Custom 3D Model”.

3D View - Use Custom 3D Model button

Upload the GLB file of the 3D model you want to use as the 3D view.

Add pointers to 3D Model

Open the GLB file with Blender.

For each Room you want to show inside your 3D model, add an Empty Single Arrow object and position it correctly into the scene.

Blender - add Empty Single Arrow object for each room and position it

Set its rotation values to X: 0, Y: 90, Z: the direction from where the photo was taken with yaw set to 0 (the center of the panorama).

Blender - set rotation values X:0, Y:90, Z: photo direction

Within the custom properties of this object, create one of type string called id_room and set the ID of the room in it.

Blender custom properties - create id_room string property with room ID

Export the GLB file, selecting in the settings to include the custom properties.

Blender export GLB - enable custom properties in export settings
Final custom 3D model displayed in Render Walk 3D View