Routing calls

Hi,
Is it possible to dial an external number and dial an extension both seperately and route them when necessary. Which command can be used for routing both?

The 555 area code cannot be issued per NANPA and INC (atis.org) guidelines (www.nanpa.com), but the 555 Exchange (NXX) is now issued and should be opened up in all geographic area codes (NPAs). National 555 line number assignees get all geographic area codes in World Zone 1 at once.

The official 555 NXX Line Number Assignee list is at

nanpa.com/number_resource_info/555_numbers.html

Huh? Anyway, re OP

What does this mean? What exactly do you want to achieve?

Hi,
I want to call an external number and only when somebody answers i will make a call to an extension and route it to the answered call. This is what i want to acheive.

Google asterisk call file. Also known as auto dialout.