iMac not connecting to Internet.

i have checked my network connections and it says I am connected to wifi and ethernet. However, I cannot load safari, chrome, Firefox, iTunes, appstore, or my daughters game minecraft. I believe it has to do with my wifi or Ethernet because the same things happen on my iPhone while connected to wifi. But then again, when I disabled my wifi on my computer it still did not run. I have become very impatient with this because we can't even load a system update or Apple.com! I have cleared cookies and website data, restarted and completely shut down the computer, changed to OpenDNS servers, and logged in through other account users. We even cleared up some space on our computer. We were planning on downloading CleanMyMac if that was the problem but we can't even get to the website.