Is under attack safe to enable

We have seen cloudflare provide under attack mode . Please clarify below points:

  1. Is it safe to enable under attack mode always ?
  2. Is under attack mode blocks Google bots ?
  3. Also is there any important things to note before enabling under attack mode ?

Thanks

No, the I'm Under Attack! security level will still allow good bots afaik.

You should use High unless your site is actively under attack. From Understanding the Cloudflare Security Level:

Only use I’m Under Attack! mode when a website is under a DDoS attack.

I'm Under Attack requires visitors to pass an automatic JS challenge page. From Understanding Cloudflare Under Attack mode (advanced DDOS protection) :

Browser JavaScript and Cookie support are required to pass the interstitial page.

This means some visitors won’t be able to visit your site at all while others may get tired of waiting and leave.

Visit https://support.cloudflare.com/hc/en-us/articles/200172676-Understanding-Cloudflare-DDoS-protection for more information about DDOS protection with Cloudflare