Need Help setting up a Asterisk ubuntu box to sell voip

good day , could someone please send me a link or info how to setup my asterisk ubuntu box to sell voip over my netwerk

my suppler wants to supply me with a sip trunk that i will have to add to my pbx , and then ill have to connect multiple clients with IP phones back to my pbx

i need info on how to config my box to do that .

Best Regards