Support Center under Email Channels display the Support Site URL of the registered company 

For example :- If user have registered company "Help" for azuredesk than Support URL will be help.azuredesk.co

Logo Image :- It helps user to customize the logo its Support URL

AzureDesk Account Name:- 

Unlimited Mail Box

AzureDesk has its own email domain and also supports unlimited email address under that domain. When user signup at AzureDesk than by default support email id is created support@companyname.azuredesk.co

Unlimited mail Box supports unlimited email addresses where user can add the emails address to the email box & all the emails to those addresses gets converted into a ticket in AzureDesk. So you have all your emails at one place. Also since all the emails gets converted into the tickets there are no chances of missing out on any email.

In AzureDesk --> Channels Menu --> Email helps you to add the NewMailBox.

Once the email address is added than all the tickets forwarded to those email address is converted into the tickets & is displayed on AzureDesk Display Ticket page