I’ve tried adding my site to directories and posting on Medium/LinkedIn,
those aren't powerful links. They might give you some traffic and a bit of authority (very little of it), but they won't move the needle.
definitely
There is an art to building links that rank instead of tanking your site, and while I'm not an expert on link building (I've been out of the game for nearly 5 years), I can point you to this guide on how to approach link building, written by someone who I consider expert:
https://www.blackhatworld.com/seo/guide-how-many-links-per-day-week-or-month-should-i-build.1502403/
but I'm unsure how people actually obtain them.
in so many ways that I don't think I can list them all here... or that I will even remember them all.
But before building links, you need to understand a few things, such as...
1) google hates link builders despite of what they might say. And, as such, they're on a secret mission to exterminate all link building methods and to prevent everyone from building links because the backlinks are heavily influencing google's results, which is something that google hates because it messes up their perverted goals.
And the reason I'm saying this is because - being on a mission to get rid of all backlinks, and all backlinkers - google are devaluing most of the backlinks that are easy to get, free to get, or both.
So, if you approach link building (especially for ecommerce sites, which are usually hard to rank for newbies) with a "get as many free backlinks as you can" mindset you most likely won't get any decent rankings since free and easy to get backlinks have no power for the most part.
There are exceptions to this, of course (niche forums, for example, or social signals - although I personally don't consider these backlinks - from real and established accounts with high engagement, or brand mentions on various forums or UGC sites, etc).
But - while these links are free - they are not easy to get since you...
- either need some sort of access to those real and established social media accounts, which is not easy to do if you're not into social media or if you don't know what you're doing
- or you need to be popular, hot or trendy in order to have people willingly mention your brand, which - again - is not easy to do for most newbies
- or, like I said, you need to spend time on niche forums to engage with the community and find an opportunity to drop a link somewhere that attracts clicks (which is where the magic of forum links happens). And while forums links are both free to get, and easy to get, they are definitely not fast to get since new accounts can't drop links wherever they want. So, in a sense, these links are hard to get actually (which is why they cost a lot of money when you check marketplaces for such links)
With all of these out of the way, it's obvious that the links that are most valuable today are the links that cost a ton of money, are hard to get, or both.
And again, I am not speaking about ALL case scenarios (I had to specify this for those who might jump at my throat with excuses "bUt I hAvE rAnKed WiTh OnLy FREE bAcKliNkS, sO yOu DoN't KnOw WhAt YoU aRe TaLkInG aBout...", there are definitely exceptions to the rules, but I'm not addressing those because if I did, I would have to address every single exception that google makes to every site, every niche, every keyword, and so on, and google have a ton of rules and filters for almost every scenario, so yeah... I was speaking in general)
2) well, I already forgot what point 2 was, sorry about that
But anyway, with point 1 being clear (hopefully), some of the many ways in which people get links that matter for their sites are these...
- they outreach to relevant sites in their industry, offering something of quality (usually content) in return for a backlink
- they pay for backlinks in marketplaces like Adsy, BHW, etc
- they buy quality press releases (a well-crafted and well-placed press release can attract dozens or 100s of links organically, and even get an influx of traffic into their site for days if the topic is hot or trendy... I don't think that PRs will work well for ecommerce sites though... at least not for common / unpopular ones)
And I'm sure there are more ways in which they obtain links (human creativity knows no limits

) but I'm pretty dreamy today, so I forgot them...
But yeah, this is - in a nutshell - how it works. Free and easy to get links are continuously being slaughtered by google, although some of the free links could work in certain cases (edu / gov links for example, or maybe even PDF submission links, although I've not tried this in years, so I can't vouch for their validity anymore, but they might still work in certain cases...)