In order to connect to a website, you need a server/FTP address, a username and a password, setup your ftp server using Dreamweaver.

Select Site > Manage Sites.
Click New and select FTP & RDS Servers. (or)

Select Site > New Site...
Select the “Basic” Tab and then click on “Create an FTP or RDS server connection”

FTP (File Transfer Protocol) is used to transfer data from one computer to another over the Internet, or through a network.
RDS (Remote Development Services) is used to provide remote HTTP-based access to files and databases.

Setup your ftp account:

Name – your website name for your information only
Access type – select FTP note: the RDS is use for remote development
FTP host – put your FTP host is the full Internet name of a computer system, such as ftp.webdesigningco.com

Note: If you don’t know your FTP host, contact your ISP (Internet service provider)

Host directory - where you can store documents that are visible to the public, for example Public_html, html or www etc. if you don’t know this live as it was.
Login – your ftp username
Password – your ftp password
Save – Check the box if you want Dreamweaver to save your password permanently.

Check Use passive FTP
Check Use IPv6 transfer mode If you are connection to an IPv6 (Internet Protocol version 6) enabled server.
Check Use Secure FTP (SFTP)

Before finishing it, check the information you type is correct, and then click on “Test” to check the ftp service is working or not. If you get this message it means you succeed, now you can directly work from your ftp server.

If you get any error it means the information you used was wrong, recheck information you type.

Now you can start working with server file.

If you want to edit ftp configuration settings,

Select Site > Manage Sites
Select the website which you want to edit and then click on "Edit..." Button, make necessary changes you want and closed.