Adding friends and writing private messages

Hello everybody, first of all I would like to appologize if I posted a new topic into a wrong section, if I did, please move it or remove it

So the thing I wanted to ask is, is there a way I can add some users as "friends" and writing them a private messages? Thanks.

For the time being it seems Steam PM is the best solution, I have my Steam profile linked in my ReShade Profile Page, feel free to add me and if you need a hand with something (OmnipotusX)