أحسن الله إليكم A person suffers from intrusive thoughts that insult Allah and islam,he fights those thought but sometimes fails and lightly laughs and finds it abit funny so he gets scared and thinks of the thought again to analyze himself if he finds itfunny but the same thing happens,is this kufr

This is OCD, and it is a form of waswas, which I heavily recommend you handle by doing what the Messenger (sallallahu alayhi wa sallam) told you to do: say "A'udhu billahi minash-shaitanir-rajim" and stop. Don't indulge in them whatsoever, because if you entertain these thoughts in any way, shape, or form, they can ruin your life. You are constantly going to think that you are a kafir or that something is wrong with you, despite the fact that there is nothing wrong with you. Everybody has these thoughts; it is just that you are reacting differently than everyone else. You are overthinking them and not getting rid of them or stopping like the rest of us do. When you aren't able to stop, you fall into this type of OCD. My advice, of course, which I always give first and foremost: 1. You have to go to the people of the field and the specialty, like psychiatrists, psychologists, and the like. 2. You should ask for their recommendations. 3. They will give you a plan that will help you. Remember not to get carried away or to even think about these thoughts. Stop them, just as the Messenger (sallallahu alayhi wa sallam) told us to do.