Website inaccessible

Yesterday, my website was inaccessible due to a domain issue, and I also had to change my web certificate (SSL) to Netlify's built-in SSL (Let's Encrypt).

I have learned about Netlify CDN & Cloudflare CDN. As for speed response time, I cannot use Cloudflare CDN under Netlify CDN. I want my website to be as fast as possible, so yeah, I cannot use Cloudflare CDN anymore. I only use Cloudflare service for storing all my DNS records.