Wordpress Site Optimization with Vps, Plesk, Cloudflare, and Url Cleanup in Google Console

Hello everyone, thank you very much for your attention to my project.
Please read carefully before responding!
I am looking for someone experienced in VPS server configuration, specifically with the Plesk panel, to optimize a WordPress site that uses an Nginx server and Cloudflare security.
Here are the main issues I am facing:
1. Persistent object cache warning: I receive the following message: "A persistent object cache makes your site's database more efficient, resulting in faster load times because WordPress can retrieve your site's content and settings more quickly." I haven't been able to configure this correctly.
2. Drop in organic traffic: After setting up Cloudflare for security and caching, I noticed a significant drop in organic searches, even though page load speeds (especially for blog posts) have improved. I'm unsure if everything is properly optimized between Plesk, Cloudflare, and WP Rocket.
3. Image optimization: I'm not sure if I need to use Imagify for image optimization or if the current setup is sufficient.
4. Second page load issue: It seems that something might be wrong with the cache configuration because the second page takes longer to load, which might be affecting overall performance.
5. URLs registered by Google Search Console: The Google Search Console is registering URLs that no longer exist, such as old AMP pages. These URLs might be stored in site folders or in the database, and I would like to clean this information to prevent SEO issues.
I need someone with expertise in the areas mentioned above to ensure the site is configured for optimal performance, taking into account the plugins and resources already in place.
My goal is to have a fast and efficient site in every way possible.