You can create a website using wordpress cms for free. You only need a domain name and hosting space to create your website. Hosting provider will provide you hosting space and related software tools to manage your website. Creating 3D floorplan is not part of hosting and hence they will not provide same. You can get 3D floorplan from your graphic designer and upload same at your website. Your visitors can also create and upload 3D floorplan if you grant him necessary permissions. Alternatively, you can search for plugins to generate 3D floorplan for you and your visitors.
You can get affordable domain names, reliable web hosting packages from http://www.webstation7.com which is essential for creation of your own website.
Once you get domain name and hosting plan, just visit wordpress.org to download wordpress cms for free, upload entire cms at your hosting space and then open installer file in any browser like yourdomain.com/install.php and follow onscreen instructions to complete installation. Now you need to customize your website using themes for design issues and using plugins for functionality related issues. You can check for suitable plugins to generate 3D floorplan for free or paid.
Once you finish installation and customization, you can manage your website from yourdomain.com/wp-admin.php for all management issues on regular basis as per your requirements.