Question: I said or it came into my heart that Islam doesn't make sense but I didn't act toward it. Is this a kufr act? And while I was watching a TV show its was a Hindu show there it was about cleanliness the boy said that soon our city would world's most cleaned city but after awhile there came a monster who made it unclean so I said if Allah's doesn't will something it doesn't happen but it's a Hindu show so I said it not about Rabb so did I do a sin? Did I do kufr? How should I repent!??

Answer: 
If you did not act upon what you thought there is no sin on you. Ask Allah to guide you and seek information on Islam from authentic sources so that your doubts can be addressed. Be patient as the answer may not come right away.
Such thoughts are not taken on you.
The biggest problem in our islamic world is that we prohibit such questions. It is totally legal to ask, but you have to direct your question to specialist. Specially when it is related to faith and Allah acts.

Be more specific, what exactly motivated you to think that Islam does not make sense?

You have to distinguish between two things, willing and satisfaction.

As you said, if Allah does not will something, then it will not happen. So WILL is about good and bad. When people choose kufr, this is totally by Allah will. Allah give them the ability to choose kufr. However, this not to satisfy Allah. Quran said that.

> 
> قال تعالى: "إِن تَكْفُرُوا فَإِنَّ اللَّهَ غَنِيٌّ عَنكُمْ وَلَا يَرْضَى لِعِبَادِهِ الْكُفْرَ وَإِن تَشْكُرُوا يَرْضَهُ لَكُمْ وَلَا تَزِرُ وَازِرَةٌ وِزْرَ أُخْرَى ثُمَّ إِلَى رَبِّكُم مَّرْجِعُكُمْ فَيُنَبِّئُكُم بِمَا كُنتُمْ تَعْمَلُونَ إِنَّهُ عَلِيمٌ بِذَاتِ الصُّدُورِ" [الزمر : 7]
>  ترجمة للهلالي-خان الآية 7 من سورة الزمر:  
> 
>  "If you disbelieve, then verily, Allah is not in need of you, He likes not disbelief for His slaves. And if you are grateful (by being believers), He is pleased therewith for you. No bearer of burdens shall bear the burden of another. Then to your Lord is your return, so He will inform you what you used to do. Verily, He is the All-Knower of that which is in (men's) breasts." (39:7) [Translation by al-Hilali/Khan]
> 
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To repent, you should seek forgiveness by estighfar