Text: this means that the more the player plays, the more money the player gets back.

Correct capitalization: This means that the more the player plays, the more money the player gets back.

Text: i am a new member to the website. i want to congratulate you on such a fantastic

Correct capitalization: I am a new member to the website. I want to congratulate you on such a fantastic

Text: be gracious to me in the last moment.

Correct capitalization: Be gracious to me in the last moment.

Text: in the following i shall describe a new model of the sun and other stars.

Correct capitalization:
In the following I shall describe a new model of the Sun and other stars.