You don't even need to submit to any search engines these days - they'll find your site quickly. But if you do submit, only do it once ...
Don't manually submit your sites, build backlinks from sites that are already indexed and allow the Search Engine Spider to crawl your site and index it itself.
Only once or else don't submit it. Google will find your sites. Just do all the process of SEO like off page optimization, for sure Google will index your work.
search engine submisison is old schoold method which is no longer needed. since you will need to do your link building anyways, submitting to search engines will be nothing but mere waste of time on an useless process. all major search engines will find your site folowing the backlinks