Yo puedo expliquerlo en inglese ! espero que comprendes
left click the name that you want to chat with .
The profile of the person will open.
On the top right side you will find on the third line " chat now" if enabled you left clicked to ask for a chat .
If the person answers you a chat box will open and you both can chat .
You can ask also in the profile box for Adding request , at the top right again ,
the first line " Add to friends" you can send an adding request to have the person as a friend on your list .
Espero que has comprendido :)