First remember that the SIP protocol in vitalPBX 3 registers on port 5062.
If you are going to use SIP you can configure it in the same way as you did in FreePBX, for which you select SIP and then at the bottom left make Switch to Text mode and you will see the interface very similar to what you did in FreePBX.
If you are going to use PJSIP port 5060 (which is perfectly compatible with SIP). You will see in the interface the equivalences by name and it is only to be filled depending on the data that the supplier gave you.
We hope this helps you.
You can also see some examples of trunk configuration in these Blogs: