Well, the documentation covers most of this. If you are planning to do much administration I'd start to read through these. Long term this will make things easier.
For now, to check what kind of authentication your instance supports use SQL Server Management Studio to view the security properties. By default it will be "Windows Authentication Mode"; for the connection
string you supply you need "SQL Server and Windows Authentication Mode".
To find out if your server is configured to allow connections over TCP/IP, use SQL Serve Configuration Manager. There's a section that lists the protocols enabled for your server.