The best backlinks come from websites which are seen as an authority in your particular niche. If you’re publishing content on coffee, you want the biggest coffee magazines to link back to your site. The reason is that’ll give you better chances of users clicking through to your site and a stronger signal to search engine crawlers that your site is the bees knees. Oh, and this only works if you get a “dofollow” link from another site. That’s a tag which tells search engine crawlers to read the destination of the outbound link. There are various ways to measure how “authoritative” a domain is, such as Domain Rating (DR) from Ahrefs, Domain Authority (DA) by Moz, and Google’s PageRank (which is seen as a little outdated). None of these metrics give the full picture, but they can give you an idea of how influential a domain is.
Typically, domains with lots of readers (bot traffic doesn’t count) and a history of publishing high-quality content are the best ones to secure backlinks from.