I Built a search engine and I'm taking submissions were following the same meta tag rules as Google submissions are free and open for our keebu search engine below is the link https://keebu.com/submit/
I tried some basic searches relevant to my business, nothing. "Cars": nothing. Only porn had a result. "Apple" comes up with Nintendo. I get you're looking for submissions but have you done ANY indexing?
We're indexing whatever users submit so if you want something on Cars submit those websites and we'll crawl them hopefully that answers your question
You need to re-read that sentence! If I already know the site that has the answers I'm looking for I'll just go to those sites. A real search engine will index all the pages on all the sites, follow links to discover new pages and sites etc. I'm not sure that you're serious about this business.
I'd start with one topic and build a useful set of results there first. Otherwise you're asking people to submit sites before they've had a reason to use the search. Maybe add a few example searches that already return good results. That would make it easier for someone new to see what Keebu is useful for.