A second chance is quite similar to regaining trust. People earn it. I personally believe that giving someone a second chance is something to be given if you can feel the sincerity. I also believe that a second shance should be the last chance as well.

Only one chance life will give you to become a rich person if you avail it at that time you will be the one of others

There's not much context there. Depending on the situation, I think people deserve a third and forth chance too.
: )

Why it is needed to do something
to deserve a second chance?

Sorry, but I don't get the point.
???

once you found you have missed a good opportunity, then definitely you will succeeded or won't do the same mistake again

Depends on the situation, Sometimes people can mess up many chances but still get their act together and win back what they value, at others people can't even land themselves a second chance and they keep moping forever.