Please click on this link to download PuTTY directly:
Credentials to connect to your server will be available in the left column of the website: "Access to your server"
You will find:
If you can't connect to your server please check:
Your computer is connected to internet
The network (wifi or ethernet) that you are using allowed SSH (port 22) - It can be a firewall rule, ask the administrator to open it
Make sure you are copy-pasting server's credentials, mainly the password - it's case sensitive!