Seriously slow pages

I am suffering from slow pages.
I am using Simtech’s Cloudhosting and using Unitheme.
I have requested support from CS-Cart and the server manager several times, but it is not resolved.
Cloudflare’s Pro version and caching, CS-Commerce’s Html caching are also used.
Pages are sometimes fast and sometimes very slow.
Sometimes it takes more than 5 seconds to automatically load the next page of the product list
Product pages load at varying speeds, from 0.5 seconds to 32 seconds.
Sometimes it can take up to 5 seconds or more when adding a product to the cart or loading a variation such as product color.
I can’t find the cause of this problem.
Can anyone help me with this issue?

1st page loading 32s 20221231-140224 — ImgBB
2nd page loading 1.75s 20221231-140256 — ImgBB

No matter how many forums find, it’s a old.
It seems that everyone has given up.
Transformation is slow and we are not seeing any way to improve it.
Significant speed was obtained through server migration due to product page access problems, but products such as shoes with many variations still load slowly.

Even if you want to use options, options cannot be managed in inventory.
Everyone seems to have no ideas.

what about images on your pages? I had same issue but image optimization helped me lots

Convert images to webp and use lazy loading.
I moved the current server to bare metal and it has improved a lot. Was it a server issue after all?