In our lifetime we can not learn all skills required from scratch on your own. A human being has a finite number of years to live, and it is almost impossible to determine all things. So, we need a supporting entity which helps us in achieving what we are looking for in lesser time. Your mentor can tell you the essence of his lifelong attained expertise which can be leveraged to achieve your goals.
A mentor plays the role of a teacher, an advisor or a coach. Mentors develop you to make the better version of yourself continuously.
In today's world, it is easier to find a mentor as compared to ever before in the past. These days there are offline and online mentors. A person who is doing great in your field, and you see him as a mentor. Then you can follow him online, can study his articles and attend training, etc. A classic example of this online mentor is Warren Buffet. He is the God of investment and has innumerable followers who see him as an example and a mentor.
What should we look for in a mentor?
A person who is already successful in the field you want to get an expert in. You can learn lessons from failure stories of other people, but you can not consider them as mentors. A mentor should be one who tells you about the success mantras and should be on the top of the skills which you want to master.
A mentor should be an expert in his field. There are many accidental millionaires also who have no expertise in the field and can not share their success stories because their success was just a fluke instead of a well-planned set of actions. An expert can tell you the real dynamics of that field.
Your mentor should be the person who teaches you to face the fear of failure or temporary defeats. It is truly said, "failures are the milestones of success, not barriers.". Your mentor should inspire and motivate you to make you strong enough to face these defeats.
One should understand the problem first to propose any solution. So, a mentor should be a good listener who listens carefully to the mentee and understands his/her perspective on what that person wants to achieve. Only then the best solution can be provided by the experts.
A mentor should be an active learner with the updated version of his expertise all the time. These days, technologies get obsolete in days, methodologies are getting changed in weeks/months. A mentor should suggest things according to the current market scenario. Only then best outcomes are expected. A mentor who is not a consistent learner, then his suggestions will also become obsolete by the time.