Oftentimes, search engines find your website and web pages through links from other sites. They assign a “trust factor” or quality factor to those links to determine whether a piece of content is popular and should be trusted. Links from .gov or .org websites are traditionally looked at as having even more power and quality because they are looked at as strong authorities and very trustworthy due to their affiliation with the government or an association.
As often as a few years ago, brands could easily manipulate the link factor. There were all kinds of link networks and vendors that you could subscribe to that would essentially allow you to “rent” links in their website network. In essence, you were buying links artificially. There have been several algorithm updates since then, and search engines have penalized sites that seem to be acquiring links from low-quality sites. The best way to build links to your site is to do so organically and to be deserving of them by providing useful, high-quality content. This requires long-term, strategic thinking sometimes it may be better to employ the services of an SEO expert for this. It also requires a combined approach that leverages online assets a brand may create outside of their website on other high-traffic websites and to embed links in those assets that go to their content (that they're trying to rank).
Additionally, brands need to be vigilant and regularly monitor that low-quality sites aren't pointing links to them; these are also called toxic links. Fortunately, search engines provide a link disavow option via their Google Search Console or webmaster website monitoring tools, which allow you to mark incoming links as low quality and instructs them to “disavow” or essentially ignore them. Many SEO Agency tools have a feature that checks the quality of links pointing to your site and provides you with a list that you can upload into each search engine's platform to disavow poor-quality links.
To boost links, nothing works better than offering useful and unique content. I once had an automotive brand that we were working with that was looking to build links. When we started working with them, their site had only about 1,200 links pointing to it. This is incredibly low considering many websites in their industry had more than 1 million links pointing to them. We were at a major disadvantage to ranking well and leapfrogging the competition. We conducted a content and search term analysis to determine what topics people were searching for and provided a gap analysis to show where they were missing content. We built many “how to” and other types of help content.