I'm guessing you've not tried looking around because you want everyone to do your work for you, this question has been asked
alot of times and there lots of controls out there that can do what you need with a bit of work.
There a some controls that have a cost and some that are free.
One of the free ones is:
http://orgchartwebcontrol.codeplex.com/[
^]
I found this by simply searching for "
c# creating a horizontal tree view
" on
Google (your friendly neighbourhood search engine).
This lead me to this previous question on this very site:
Horizontal treeview control[
^],
where one of the answers linked to this other question, again from this site:
C# Organization char[
^]
and hey preseto lots of links to various possible solutions to this very issue.