ip addresses

I checked log files and found more IP addresses from Netherlands are attacking my server and cause my websites overload or can not load. I want to use a tool or Cloudflare to block all IP from this country or countries which having IPs attacking my server via DDOS attack. Is that possible?

Can any one tell me the way on how to detect ip addresses ddos my websites and using cloudflare to block them? or should I just enable ddos protection from Cloudflare is enough?