My team wants to move news section of our website to subdomain ex "news.website.com" does it affect SEO? Can anyone tell me pro and cons of this thing?
One thing about subdomains is that they will be treated as an individual domain, so you may be splitting you linking power across two domains instead of just one. It could affect your domain authority since you will essentially have two separate websites instead of just one.
It's not necessarily a bad thing, and there could be cases where this may even be beneficial (in cases where the subdomain gains better niche authority).
If you do move the content you absolutely need to 301 redirect all the traffic from those old indexes to their new location. Failing to do so will undo any previous backlinks and SEO power that your news section once carried.