How do I get phone number and that will link to extentions

[kingslinkven]

How do I get phone number configured to my hand set phone.
Als could any one lead me to an ISP who can partner with me and make
me sales representive.The ISP will give the following serviceINTERNET ACCESS,VOIP,cable TV with broadband on V-SAT to cover 10,000 miles orbit.
Thanks