The difference between DoFollow and NoFollow links is that...
Dofollow links pass page rank (link juice) to your website.
Nofollow links don't pass any link juice but they pass high authority signals (citation flow, trust flow, page/domain authority) to your website.
So they're both valuable for your seo rankings and you need a good balance for both Dofollow and Nofollow links. If you have a lot of Dofollow and less Nofollow that will look suspicious to search engines and might harm your rankings.
But if you have a lot of Nofollow and less Dofollow that will not harm your rankings and it will increase your website's authority.