Connection refused when i go to web

When I try to install cozy, I go to web and put my IP and appear a connection refused, I am new in this topics and i follow the instructions to install, i installed it on a Raspbian

And i have a trouble with this part -> sysctl -w kernel.unprivileged_userns_clone=1

Cozy can’t use IP directly, you must order, configure and use a real domain name for that, pointing to your IP address.
But if you catch a connection refused on the IP, you also have a setup trouble somewhere, at least you need to have a cozy not found page.