Generally speaking, Google does not like directory sites too much. Some perhaps. However, most are generally either low quality or spammy or even replicated information that can be found everywhere. For back link building, using directory sites is not recommended. This was all the rage way back when. But not today and should be generally avoided.
Create organic inbound links (back links) from higher quality content sites with links preferably in the content itself or immediately following the content. Do not go for the low hanging fruit that anyone can do for themselves. You will simply be another sheep in the herd. Do not be a sheep. Be a wolf.
Please remember that many SEO sites are junk. Why? Because too many are parroting content with no real research. They are designed as "me too" sites trying to carve out a segment of the SEO pie. Many repeat bad advice and too many have old advice that were trends that will get you into trouble. Keep in mind that most SEOs are not technical people and do not understand search and the technologies behind search and therefore cannot understand the nature of a search engine. Always look for the best information out there, not advice, that is within the past year or so. Not older posts and not sites that repeat what everyone else says. These are the guys that tell you to create links using directories. Stay away from these sites. Please.
When in doubt, ask here before doing anything. We are real experts and can point you in the right direction.