Why is it taking more than a minute to Load my site when I switched to using cloudflare?

So this is my website: https://therevisionist.org/
It usually takes 1-2 seconds to load. But after activating my old cloudflare account to siteground hosting, now it takes more than a minute, or doesn’t load. Why is that the case? Did I configure something wrong?

Please let me know what information you need to see to help me troubleshoot this problem! Much Obliged!

I got a 524 for one file, and then a 524 for your site when I reloaded.

So what could be causing this problem? Thanks.