Smoking is haram and it invalidates your fast because it reaches the stomach and the inside of the body. Everything that reaches the stomach and the inside of the body breaks the fast, whether it is beneficial or harmful.

Committing sins during the day in Ramadan, such as swearing or insulting others, does not break the fast but it detracts from the reward for fasting.

Matters that break the fast only break it when three conditions are met: 1. Knowing the ruling 2. Not forgetting that one is fasting 3. Doing it with free will.

Being given medicine via injection does not break the fast, whether it is intramuscular or intravenous, so long as the injected substance does not provide nutrition.

If the face mask made of honey entered your mouth and you tasted it without swallowing, that does not affect your fast.

If the fasting person detects the taste of blood in his throat that does not affect him even if he swallows it, but if it comes up to the mouth then he swallows it, he breaks his fast.

If your period begins before sunset, even if it is a moment before iftar, your fast is invalidated and you have to make up that day.