In order to be a good medium, the psychic gift must be well developed and you need the ability to tune in to the spirit entities. Not everyone has this gift. It takes years to develop mediumship to a high degree. Dedication to sitting for spirit is a must.
Working in this way is not a game, nor indeed, is it entertainment. It is also not a way to get rich quick, or in fact, get rich at all. If you wish to make big money then this is probably not the life for you.
A medium can communicate with loved ones who are in the spirit world by using their special senses to pass on information to you from the loved one, to prove to you that the loved one still exists even after their bodily death.
Therefore, it does prove that there is life after death.
Everyone of us has psychic ability to some extent, but choosing to use it is always an option and never compulsory. Once the gift is developed, it can be a far more useful and interesting gift that can lead to other, higher, things.
A psychic can give you information that is gleaned from your aura, or from within the vibrations around you. The details given in the message will already be known to the sitter, because all their experiences in life are around them for a good psychic to read. A psychic does not connect to the spirit world at all, and therefore cannot receive messages from spirits.
You may not know at first if you are mediumistic or psychic, and this is not something that you get to choose, as you are either mediumistic or just plain psychic. Though some will say there is nothing plain about being psychic. There is something really exciting about mediumship though.
You will soon learn how to spot the difference between the two gifts, but just remember, you certainly have the psychic gift like all of us and if you are also mediumistic it is a bonus which you will become aware of during your development. First though, concentrate on developing your psychic ability.