I can not access to the website with a public IP

I am setting up a new EC2 with Ubuntu, but I am getting a weird error and it is that I can not access to the public ip, it says refused connection.

My security group has these ports enabled:

HTTP    TCP 80  0.0.0.0/0   -HTTP    TCP 80  ::/0    -SSH     TCP 22  0.0.0.0/0   -SSH     TCP 22  ::/0    -

My public is: http://3.16.154.123/

The EC2 interface is running, it's in green and that is the public ip which it gives me... so I wonder what is the problem? why can I not access to the public ip? why does it say refused connection? or more clear this error ERR_CONNECTION_REFUSED

Thanks.