CPU and RAM problem

So, I’m having trouble finding an error on my website. I don’t know what’s causing it, but I’m experiencing such CPU and RAM spikes that are taking my server offline (see picture): https://ibb.co/wQ21q8C

I didn’t have this issue before. It started around the end of August (see picture): https://ibb.co/VDD3WDc

I’ve owned the server and the website for about a year now, and I didn’t have this problem before. I host the server with Hostinger, and they’re telling me it’s because the website isn’t optimized, which is nonsense since these problems started out of nowhere. I suspect there might be a conflict between plugins or the theme.

Also, most of the LVE logs are related to index.php as well: https://ibb.co/2smcMWx

I also have this big amount of requests that were managed by cloudlflare: https://ibb.co/dgL9LQb

Is there someone that can help me?

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