I'm currently on macOS High Sierra, i downloaded the update last night and since i cannot connect to any browsers. I can ping sites like google, but that's about it. I managed to get a browser called "Chromium" working for a short while, and now i can't get anything to work.
Did you restart your Mac?
Here are some additional troubleshooting steps to follow, in no particular order:
Determine if the problems exist in Safe Mode. Then, restart normally.
Needless to say, if you are using any non-Apple "anti-virus", "cleaning", or "Internet security" products, anything at all in that broad category of utterly useless garbage, don't. A lot of things won't work if you do.
If you don't get anywhere, you can use the following procedure to determine if the problem is internal or external to your Mac. Causes may involve your router, your ISP, the DNS Server(s) it uses, or certain user-configurable options.
Determine if the problem persists while using Safari in that mode. After that, restart your Mac normally, and reply with your observations.
Back up your Mac prior to making any changes to its file system. To learn how to use Time Machine please read How to use Time Machine to back up or restore your Mac - Apple Support.
Connected to the internet but cannot use any browsers?
