Lushimania, yes this site has an abundance of knowledge...
First of all, please create your own tread for your questions.
Secondly, go to the set, and do a FEATURE * 0 and press the handsfree button, see if it is handsfree - it will say that on the display, if there is no handsfree it will show up as the extension number of the set.
Under TERMINALS&SETS -> SHOW SET:___ (extension of sets you want to change) -> CAPABILITIES [enter]-> keep hitting next till you see HANDSFREE: change to Auto , press Next to save, and change the HANDSFREE ANSWERBACK to yes. Press the Next button to save changes. See if there is an UPDATE on the screen, when the update is done - Voila you should have handsfree capabilities now.