Dont know how to set

It varies slightly from model to model. But basically, you run a phone cable from your wall to the line port on the printer, you can run a line from the phone port to an analog phone if you choose. You put your job face down or up on the printer to scan, dial your number, and hit send.

Some complications:

1. You may need to dial 9 to get out on a company network.
2. Digital phone systems, DSL, and IP phones don't play well with Fax lines.
3. In an All-In-One solution, you may have to hit a FAX button to be in "Fax mode".

As for number of rings to pickup, etc. You need to consult the manual for your specific printer/Fax.