i have already install Asterisk, i have to make a PABX system by using two soft phones, what are the forums to start my project
Hmmm what is your actual issue?
Asterisk Biz & Jobs is the only forum that covers that nebulous a requirement. You won’t get an answer on it, but people will offer their paid services.
If you don’t want to pay, you should go to asteriskdocs.org/.
As already hinted, once you have specific questions, that can be answered quickly, but are not obvious from the documentation, you should use this forum.