Question mark shown over ethernet icon

The question mark typically means that the computer is connected to the router but does not yet have access to the internet. In many cases, this is because DNS nameservers are not properly set. Check:

ping -c3 8.8.8.8
ping -c3 www.ubuntu.com

If you get ping returns from the first, but not the second, then DNS resolution is not working.

If you wish to use a static IP address, you may do so by editing connections in Network Manager. In this case, if you set up a fixed address, you are responsible to specify DNS nameservers, as well. I suggest:

Of course, substitute your exact details here. Reboot and test:

ping -c3 www.ubuntu.com

You should be all set.