When using direct quotes, you must properly punctuate them in accordance with where you have placed them in your own written text. Placement of the comma is often particularly confusing since you might wonder if the comma goes before the quotation mark, after the quotation mark, inside the quotation mark, or on the outside.
In American English, the comma always comes inside the quotation marks. Use a comma inside the quotation marks when followed by an interrupting expression. Then use a comma after the expression, outside the quotation marks, before concluding the quotation.
In British English, periods and commas only go inside quotation marks if the original quoted material also had those punctuation.
I hope this helps!.