How can I use the GUI to set an trunk line to go directly to an extension? And just as backwards to the outside as well?
You set an inbound route to point directly to that extension only and you set the outbound caller ID on the extension that you want it to push through on outbound calls.
I’m a beginner, please show me a guide with pictures where I can set this up. I have FreePBX 16 with Asterisk 20
https://sangomakb.atlassian.net/wiki/spaces/PG/pages/26116316/Inbound+Route+User+Guide
There are also many guides on YouTube where you can learn how to set up a FreePBX system.