letters overlapping on websites

Safari/Preferences/Advanced and make sure Never use font sizes smaller than is not checked.

Safari doesn't load a page or webpage items are missing

Try setting up another admin user account to see if the same problem continues. Please post back on whether or not this worked. Also try the Safe Mode. Please post back on whether or not this worked.

Isolating an issue by using another user account

Safe Mode - About

Safe Mode Startup – El Capitan. also Sierra

If it works in the Safe Mode, try running this program when booted normally and then copy and paste the output in a reply. The program was created by Etresoft, a frequent contributor. Please use copy and paste as screen shots can be hard to read. Click “Share Report” button in the toolbar, select “Copy to Clipboard” and then paste into a reply. This will show what is running on your computer. No personal information is shown.

Etrecheck – System Information

You realize that this is the Pages for Mac support community, that Pages is a word processing applicaiton, and has nothing to do with website, or webpage design?

What default encoding have you set in your browser preferences? Mine is Unicode (UTF-8). In Safari, that would be under the Advanced tab. Is the Style Sheet selection set to None Selected?

Ignoring you are in the wrong forum:

Which browser? All browsers? Only some browsers? Only one browser?

All websites? Only one website?

Narrow down the problem and try and eliminate the possible causes.

Take a screen snap: command shift 4 and drag over area, and post it with the camera icon.