Google do not read sitemap file and index pages

Hi. I have a website and I created some thousands blog pages for the site. After some time, I removed those blogs because I thought the blog pages do not have good quality. It leaves a lot 404 errors in Google Search Console. I create a new subfolder and create some high quality content for the website. I submitted the sitemap of the new subfolder but Google no longer index the blogs in my new subfolder. It is strange that if I use a subdomain, it can index pages from the subdomain. How should I handle this issue? Should I remove the domain from Google Search Console and then add it back? Or I have to use a subdomain?