no one can say for sure until they audit your site, but it could be any of these reasons:
- your site is not indexed yet (indexing is very hard / slow these days)
- your backlinks are not indexed yet (if your site is the one in your profile then you're in a pretty tough niche, in which you can't rank without a lot of quality backlinks, and if those backlinks are not indexed yet.... well, you can see where the problem is)
- as mentioned above, you're in a tough niche, and ranking in such a niche takes time, you might not be able to see rankings for 1 year even
- the keywords you're trying to rank for are tough, in which case you'll need a lot of quality backlinks and to also play the waiting game
These are just 4 reasons that came off the top of my head and without auditing your site, but there could be other reasons, as well which might, or might not depend on you. Did you submit a sitemap to your GSC by the way?? Because once a sitemap is submitted Google will tell you a few things that could be wrong with your site.
Also, no matter how competitive the niche is, targeting long tail keywords is usually a good approach to ranking relatively fast (within 1-3 months), so you might want to create a blog, find 100-200 long tail keywords with at least 10 monthly searches each (but which are easy to rank for, this is very important because there are many LTKs that are hard to rank for) and publish content around those keywords and then index it, and more often than not some of those keywords will start ranking outright and without you needing any backlinks. And then find more keywords, publish more content, etc... rinse and repeat until you rank for lots of keywords to pick google's interest (google likes popular sites and if your site starts ranking for 1000s of keywords and gets good traffic constantly they'll start rewarding you with even more rankings and traffic, and if you also build some quality links to the important pages of your website while publishing content this will also increase your domain's authority even more and, when combined with the LTKs strategy, you will start ranking for more and harder keywords. This approach usually works well in competitive niches, but like I said, it takes time, so you should not expect too much in the first 9-12 months)