At the moment we provide both username / password authentication and IP authentication. You can choose whichever you would like to use on your dashboard. By default you will see your list of proxies with login / password in the IP:port:username:password format.
However, you can also add up to 20 authorized IPs and authorize your proxies this way. If you do that you will only need the list of proxies with IP and port. For convenience, you can deselect the Proxy Credentials as shown on the picture to remove username and password from the list.
If you don't know which IP to authorize for proxy usage, you can look it up on the websites like https://www.whatismyip.com/