If a link is set to nofollow, it means Google bot won’t crawl the link and won’t pass any link juice.
Dofollow link passes link juice and they definitely help you much, in order to achieve good page rank.

Nofollow links attributes do not allow search engine bots to follow link.That means if the website owner is linking back to you with nofollow attributes, it does not pass on link juice. Only Humans will be able to follow the links. While on do-follow links it is completely different from No-follow links.

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Dofollow links will be crawled by search engines and will be considered as a backlink for the website.Nofollow links will not be crawled by search engines but can help to increase the traffic to the website.A website should have a combination of both do follow and no follow links for better ranking and traffic.

Even on nofollow links the anchor text can be helpful