Prophet Muhammd (pbuh) said: Gibril told me to give my nation the glad tiding that anyone who dies believing Allah has no partners, he will enter heaven. Prophet (pbuh) asked: Even if he steals and commits adultery, he said yes.
Fasting is for Allah, and He alone will reward for it. There are 2 types of happiness for the fasting servant. The smell of the breath of the fasting person. If you are fasting do not get angry and do not fight.