I can provide you with a link http://www.englishpractice.com/punctuation/punctuation-full-stop-comma-semicolon/

i'll write some examples yes, i'm happy. no, he is sad. come here, Sarah. open the window, please. i'll buy tea, coffee, sugar and milk. although he is rich, he is sad. if i were you, i'd see a doctor.

Commas are used to separate groups of actions. Such as: "He hit the ball, dropped the bat, and ran to first base." The last action of the sentence must have the word "and" infront of it. You can also use commas to connect two independent clauses, such as: "She is a good dancer, but she fell during her performance." Commas are used after surprise/emotive words such as: "Oh, he likes squid?" or "Wow, she is so amazing!" You can use commas to introduce information about a proper noun: "Chicago, also known as The Windy City." I hope that helped. I'm sure there is more you can dow tih commas, but this is the extent of my knowledge.

just notice to put a space after the comma