I Need help after I update my mac to High Sierra

OK, I misread your post. So it's a Safari issue since upgrading to HS. See these support topics.

If Safari doesn't load a page or webpage items are missing - Apple Support

Safari for Mac: If Safari can’t open a website

What model/year Mac?

What happens when you try to navigate to the sites?

What browser?

Are you running any third party apps that claim to protect, clean?

If your Mac meets the system requirements you can use this link to download it:

Get macOS High Sierra

System Requirements:

How to upgrade to macOS High Sierra - Apple Support