Overall, your sentence structure lacks clarity and coherence..

I will try to make your sentences more understandable here..

"Cream Always rises to the top"

In our Pakistani society, leg pulling and words of discouragement are often used for counterparts.
- The society in Pakistan is plagued by the use of discouraging remarks and leg pulling.

We have evolved as a selfish community, with the passage of time, and the focus of individuals are mainly on their own self interest.
- With the passage of time, we have evolved as a selfish community where individuals only focus on their personal interests instead of working for the betterment of the society they live in.

Somehow, the roots of this ill behavior can be accredited to the feelings of competition forced into young children in joint family system.
- The root of this issue can be attributed to the feelings of competition and animosity between children living in joint family systems. (Please note: When you are saying something like this, it is better to refer to the source)

Nevertheless, parents and teachers also, by their negative talks and baseless criticism, creates a negative mindset in individuals when it comes to appreciate someone.
- Parents as well as teachers are to blame for the negative mindsets among children since they seldom appreciate what children do.

This leads to a circulatory transfer of this ill from parents to their children, children to their children and so on.
- Hence, the negativity is transferred from parents to children and teacher to students alike, leading to negative mindsets among the next generations to come.

As a result, we can easily see someone with a good intellect or talent, in schools or in organizations, mostly undergoes back biting and is not much liked by others, specially, who are striving to glow their presence and intend to be noticed when playing in ground, participating in class, presenting their ideas to a group.
- As a result, every school in the country witnesses intelligent students being belittled, criticized and bullied by their fellow students and teachers, ultimately destroying their self-esteem and the will to perform.

But someone, who is potentially more skilful or talented will eventually be distinguished from others and will be appreciated.
- However, there is no doubt that a person who is talented will eventually outshine others.


COMMENTS:

1. Make your sentences concise by eliminating irrelevant details.
2. Re-read your sentences twice to make sure that they are understandable.
3. Do not use vocabulary with which you are uncomfortable.

All the best.