As another adult, advice from adults doesn't really work. Why? Because being told by adults how to do this and that is all they have ever known and they want to follow their own path. Heck, some (or most) teens intentionally go against advice (advice they might even know is good) just to experience something. Like the classic "drink responsibly" and in the end the teen is blackout drunk vomiting for two days straight.

When I was a teenager I knew perfectly well that relationships come and go, it's not the end of the world and we get through it eventually, but still I felt straight up suicidal every time it happened and handled it poorly. But eventually I learned that it's okay, that being single had its own perks and even if it took more than a year eventually I found someone new. Going through bad experiences is how I learn the most, and sometimes I must go through it to actually learn.

Telling teens what to do when they are not asking for it can often come across as a nuisance, and unless they are risking injuring themselves or someone else we as adults would do better by letting them come to us if they need (unless we are their parents of course as we then kind of have to step in even when it's unwanted).