To publish a website in Frontpage via FTP you will first need to have a "web" created which contains all your website files for a single website you've created.
In Frontpage, you can create what is known as a "Web" to contain your website's HTML and image files. To do this, first select the File menu from the top of Frontpage, and select New > Web.
File > New > Web
A window will appear with many template options for the website you are about to create. After you have done this, rename the folder which the new web will be stored in to reflect a name or the domain name for your site. For example, we have entered 'johndoe.com' as the name of the folder which will be created in our "My Webs" folder on the C:\ drive.
After pressing OK, the new web will be created and you will see the a listing of the files. Go ahead and build your website from within this folder.
Publishing Web Via FTP
After you have an established website created within a Frontpage Web, you are ready to publish the website. In the future, if you wish to update your website simply make the changes to the Web which is located locally on your computer, and then choose to publish using these instructions again.
First select the File menu, and then click on "Publish Web...".
File > Publish Web
A window will appear. enter your domain name or the IP address of your server.
Next a window asking for the username and password will appear. Enter your FTP username and password. Your FTP username and password is the same as your cPanel username and password.
After clicking OK you should start to see a window indicating that the files are transfering.
Hope that Helps