I want to know do-follow link promote our rank but do some help no-follow link?

Can you rephrase that? I’m unclear as to what your question is exactly.

I saw no-follow links count Yahoo, Bing But I want to know no-follow any effected google search rank and PR?

Nofollow link does not contribute in flowing link juice and Google also does not give value to the anchor taxt of such links so they does not contribute in ranking but yes they are helpful in drawing traffic. For example: hubpage links are nofollow but you get visits from hubpage if your article is rally good.

Do follow link will bring traffic and ranking both. But no follow link will only bring traffic.

no follow links can only bring directed traffic to your website, google normally ignores do follow links how ever some seo experts argues that google do consider no follow links

Dofollow links passes the link juice
Where as the no fofllow links will not

I think no follow links count as another domain pointing at yours. Domain diversity is important too.

Live link on any web page must be do follow as google crawler gave no response or do not cached that link having no follow tag, so alawys try to have do follow links as they are more beneficial in seo.