WordPress website down due to bot attack

`Hi,

My website down on daily basis at a specific time and CPU usage 100% so that I contacted to hosting manager. He told me bot attack happen on your website so connect with cloudflare they will manage bots. Cloudflare suggest me their enterprise plan for stopping bot attack but that was very costly.
Today I deactivated all wordpress plugins and suddenly CPU usage at 30%. I have checked plugins one by one but I couldn’t find the exact bad plugin.

Is it any issue from plugin?

Kindly suggest me what should I do in this case.

Thanks in advance

The page I need help with: [log in to see the link]