360-degree videos, or spherical videos, are video recordings where a view in every direction is recorded at the same time, shot using an omnidirectional camera or a collection of cameras. During playback on normal flat display, the viewer has control of the viewing direction like a panorama.
The order is as follows: 1) upload to the site spherical panoramas from which you plan to create a virtual tour; 2) from the list of uploaded panoramas add each panorama to the virtual tour (Add to 3D tour link); 3) open the created virtual tour, edit the panorama order, select the main panorama, set transition points (tunnels).