Wa `alaykum as-salamu wa rahmatullahi wa barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
Dear brother, thank you very much for your question that shows your commitment to Islam and fasting which is a vital pillar of Islam.
In his response to your question, Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states,
Let me try to answer your questions, in their order:
1. A traveler is allowed to eat and drink if he is traveling; we have precedents for this in the Prophet and Companions; once during a journey the Prophet called publicly for a glass of water and drank it in the presence of all to see. Many of his Companions followed suit and broke their fast. When he then came to know some others were still fasting, he said, they are the ones who have disobeyed. We have precedents from the Companions that they would eat before traveling in Ramadan.
2. Now as for the question whether he can eat and drink after arriving home during the day many scholars are of the view that he needs to abstain from foods and drinks in order to keep the sanctity of Ramadan. However, there are others who do not think so. There is no evidence for this in the sources. The fact that the Companions used to eat and drink in preparation for journey proves this. Also, it does not make any sense; how would Allah allow the traveler to break his fast and yet force him to abstain at the same time; a person is enjoying the ease that Allah has granted him.
3. The same goes for the menstruating woman whose menses stopped before the end of the day; she is allowed to eat and drink; there is no evidence to enforce the hardship on her unnecessarily when she was simply making use of the allowance that Allah has provided for her. There is no evidence whatsoever that a person who is exempt from fasting is not allowed to eat or drink in Ramadan.
Moreover, if it had been necessary for such people to continue to abstain like those who are fasting, it would have been stated as such in the sources. We cannot believe that the Prophet would fail to impart such an essential piece of information pertaining to an essential pillar of Islam.
4. Likewise, if a traveler is back from a journey can have intimacy with his wife who was menstruating is free, as long as she has performed ghusl. There is nothing in the sources to forbid this. According to the rules of jurisprudence, things are considered as permissible unless forbidden.
Allah Almighty knows best.