One of the things to know you are old is when companies ask you to mentor other people.
I was asked to do this in every company I was in. Of course, it is a compliment that they value your skill and expertise, but also it is a sign that a manager role might be in your future.

It was interesting to do this in past companies. It was even more interesting when the people I tutored became my manager. When that happened I found greener pastures. Don’t stay where you aren’t appreciated.
Even if you don’t mentor other people at work, you often get the chance in other ways. I have shared that I have had people approach me on LinkedIn to get advice and I am always happy to give people advice on what to do. It has worked for me and it is everyone’s choice on what works best for them in their life.
It is fun to share my ideas and experience with others which is why I share here. Even if I only help one person that will be worth it to me. I want my life to mean something other than just existing. Does that sound crazy?
You can mentor whomever you want but don’t expect people to be clones of you. I like that people are unique and that I may have a small impact on their lives.