Can anybody tell me what is google news, and can we use this in SEO section, if yes then how can we submit our news ?
You cannot submit normal site to google news. IF you have any news website means you can submit to google news and take approval from it. Otherwise if your site is normal website means then write good press release and submit to various press releases websites. IF you have good press releases means then your press release will be in google news for 1 or 2 days based on your site keyword competions. I think i clarified your doubts
Also, they will not accept if your site is fully news aggregator website. You have to have many news from own author or journalist.
You cannot submit articles to Google News like you can "submit site" to search engines. Google News is an automated news aggregator as wikipedia will tell you. The service scans/spiders the Internet and its news sources and presents what it conciders to be the most relevants articles in general and with regards to any search terms you may enter.