Do you agree that selling skills are the most important skills applied in life as every body lives by selling something?

Agreed.

But many other skills also necessary along with the selling skills in life.

Yes sir.

We sell either some products or services.

The gross  monetary value of all the goods and services produced are the consideration for exchange of these.

110% agreed. The most of important aspect of sales in not profit or incentive. It's the experience of meeting with people of different thoughts  and presenting your idea , your thought through effective communication whether it is verbal or non verbal , written or gesture and with interacting yourself with your clients ,you acquire the ability to grow mutually that will not only beneficial for you but also for the people around you. 

Sales person are generally soft spoken, have a good sense of humor . So , Usually  people feels easy around them.

Yes fully agree. We all need some marketing and soft skills in the career progression cycle.

selling skills is the matter of sharing the knowledge ,knowledge have spirit ,if you don’t share it die, sharing the knowledge is in many ways such ,training ,workshop ,on board ,software etc., sharing knowledge increase awareness ,commitment loyalty, better environment & better life for people .

Yes

Sir, i agree to the fact life is just like marketing . The better you could market yourself - the better your material life is . And selling is a department of Marketing .

Yes I agree as everybody at some given point of time in their lives, either professionally or personally, need to sell their ideas or goods etc to the other.