How do I set up a website within a website with its own link bar?

[Guest]

I have a webpage that has a theme and a navigation bar. I want to set up a
separate website within that structure that uses its own theme and navigation
structure on the link bar.

 

[David Berry]

Create a sub site / sub web. Make a new folder, right-click on the folder
and choose Convert to Sub Site. Now it will appear with a little "globe"
icon. Double-click it and you can make a sub site with it's own theme and
navigation.