News : (Uncountable singular noun)/ A piece of news (its countable equivalent). Although the word news has an -s on the end, it is an uncountable noun, so:
▪ it is never used in the plural
▪ it does not follow "a"
Advice: general(uncountable, always singular) / A piece of advice: a specific bit of advice (plural: pieces of advice), for example, "Top Ten Eminem Pieces Of Advice For The Kids," this video here. ALERT!!! It´s Eminem speaking so you´re likely to hear some bad language, which you are not allowed to use in class, so you might just as well ignore it (I bet those are the words you will learn and remember...)
Click here for more examples and some practice