how to modify navigation top level

Current site is with below navigation

                                               Site(index page/landing page)   ---- Level 1 Top
Section1   Section2    Section3       Section4      Section5   Section6   Section7

For Proposed

I want to  create a directory under the current site let say " Site/abc" and move all the landing page, sections under abc directory. My question is it possible to do this way and make the Level 1 Top as abc directory’s landing page