You probably wouldn't to be fair, people just need a human to listen. I did a mental health first aid course this year, I like to think I've always been caring but that gave me some tools I didn't have, and it's been really eye opening.
Little tip
Just listen, don't try to tell them you know how it feels, just ask open ended questions that give them the space to talk, be calm, reassuring and patient, you have all the tools already,
I've been helping a girl at work with anxiety through some tricky times and I went to a disciplinary with her last week, after that she went to her boss got talking honestly and got things sorted out and is happy again and less stressed, she bought me some chocolates as a thankyou, made me well emotional lol, but it was nice to have made a difference