@fadlybiluping meta description and meta keywords are just two ways to tell search engines what your blog is all about. Search robots are extremely fast today and they detect minute to minute changes that you make to your blog. At MBT we often change the description of Blog after each 4 months to test how it is playing in SERPs so it is perfectly alright if you edit your description and replace it with one that better explains your site content.
Meta Keywords are dead now and rarely do search engines care about it, not at least Google which simply ignores it because they judge the site keywords from the content itself so you don’t need to tell the robot what your blog main keywords are because the robots will pick it itself from your menu or categories or the content itself.
You don’t need to resubmit the sitemap because Google auto detects the changes on each crawl
Your site will never disappear because of this slight change unless you add the noindex and nofollow meta tag for robots