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.
What should a person, who doubts the validity of his Wudu, or over performs it, do?
One who doubts the validity of his/her Wudu while performing it should redo it until he/she is certain of having attained purity. But, if doubt was after having performed Wudu, then he/she should not pay attention to that as doubt after the end of an act of worship does not count. This is of course in case doubt was within the reasonable limits since once it goes beyond that, it becomes a whispering of the Shaytaan (devil) which he/she should ignore as the Wudu is valid.
If someone fasts on the White Days with the intention of making up for missed fasts (qada), will they receive the reward for both voluntary and obligatory fasting?
Making up missed obligatory fasts (qada) is mandatory, and the intention for qada must be specified.
If a person makes up their missed Ramadan fasts on the White Days, they must intend qada, but they may also intend to fast the White Days, and Allah willing, they will receive the reward for both.
This is similar to entering a mosque and praying an obligatory prayer, where the person also earns the reward of Tahiyyat al-Masjid (greeting the mosque) if they intend both.
● If the person missed their fasts due to a valid excuse, they may wait and fast on the White Days.
● However, if they missed the fasts without a valid excuse, they must make up the fasts immediately and should not delay them until the White Days.
Is it permissible for women to gather in one of their homes to pray Tarawih?
Yes, it is recommended (mustahabb) for women to pray Tarawih in congregation if they gather, even if it is not in the mosque.
In fact, praying at home is better for them, as it avoids the potential concerns associated with going to the mosque.