When a website generates neither impressions nor clicks, even after optimization, the issue might not be on-page SEO, but rather indexing or external signals. I think the first things you should check are:
Is Google actually indexing your site (site:domain)?
Are there any blocks in robots.txt, meta tags, or noindex, or are canonical tags misconfigured?
Does the domain have a negative history or previous penalties?
Do you have minimal backlinks? Because without authority, Google takes much longer to index a new website.
On-page optimization isn't enough if Google can't crawl the site or if there are no external trust signals. Review these points before making any further changes.