Attack Help.

Hi. This is my first thread I do not know whether or not I am posting it correct sub-forum.

It seems that I am under attack by some computer pirates. My computer security knowledge is very poor. I cannto understand what they try to do and how they find me. So I need some help. This is the screen-catch of the problem. I do not want to be under their attack often so what should I do?

 

Thank you.

attack.png