To give more infos, direct ip is here: http://178.128.101.145/
Wordking well but if i try access with the domain sica-web.app it redirect automatically to https://sica-web.app and dont work.

Here my nginx default:

server {
    listen 80 default_server;
    listen [::]:80 default_server;

    root /home/chris/webapp;

    server_name sica-web.app www.sica-web.app;

    location / {
        proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-NginX-Proxy true;
            proxy_pass http://localhost:3000;
            proxy_set_header Host $http_host;
            proxy_cache_bypass $http_upgrade;
            proxy_redirect off;
    }
}

And in digital ocean networking:

Anyway, fixed it by adding a ssl certificate but still curious about why i was automatically in https without having installing it.