hi!
Is it okay to resubmit the sitemap again and again to google?
How does it affect the indexing pages?
Why would you unless it had errors and didn’t get accepted? Once they know where it is they’ll check it often enough. But if you’re the anxious type, why not just ping them instead?
It’s not going to hurt anything but it won’t accomplish anything either - except keep you busy.
Also, sitemaps have nothing to do with the indexing of pages, rather they help Googlebot crawl your pages. Google has stated that the indexing process relies heavily on the Pagerank.