Hi,
I don't think it is possible to create several websites with one domain name, instead you can use sub-domains or sub-directories for multiple Websites. I would suggest you to use sub-directory.
For example: Suppose you have a blog for your Website.
So "website.com/blog" is better than "blog.website.com"
There is an excellent article from the head of Google Spam Team, if you want to read more, you can continue reading at:
mattcutts.com/blog/subdomains-and-subdirectories/