Can someone who begins a voluntary fast break it?
It is preferable for someone who begins an act of worship not to break it.
Allah the Exalted has said {what means}: "and let not your [good] deeds come to nought!" [Muhammad/33].
However, if a person starts a voluntary fast (nafl) and needs to break it, they are going against what is preferable, but there is no sin upon them.
Should nail polish be removed before making ablution?
Yes, it should be removed because it prevents water from reaching the nails.
What are the disliked (makruh) acts of fasting?
● Excessive rinsing of the mouth and nose (during ablution), as it may lead to swallowing water.
● Tasting food or doing anything that may risk breaking the fast.
● Engaging in idle talk, and it is even more emphasized to avoid lying, backbiting, and gossiping.
What is the ruling on someone who fainted while fasting?
● If a person had the intention to fast from the night but then fainted during the day and regained consciousness before sunset, even for a moment, their fast remains valid.
● However, if they remain unconscious for the entire day, from Fajr until sunset, their fast does not count, and they must make up for that day later.