All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
Your questions includes two matters:
First matter: Your husband. If you had married him while you were a Muslim, which seems to be the case, then it is not permissible for a Muslim woman to marry a non-Muslim man. Such a marriage is void according to the consensus of all the scholars.
For more benefit, please refer to Fataawa 262615, 81220 and 362398.
Therefore, you must immediately separate from this man and not enable him to have sexual intercourse with you, as in this case, it is nothing but Zina (fornication/adultery).
Besides, you are not permitted to live together with him in the same house unless you are in a part of it that is totally independent and is separate with its amenities.
If it happens that this man becomes a Muslim, then it is an obligation to renew the marriage contract if both of you will to have a marital bond.
Second matter: your son. He is ruled to be a Muslim because the child follows the parent who is upon the best religion. If he reaches puberty and chooses a religion other than Islam, then he is an apostate.
Hence, we advise you to take care of him and supplicate Allah to guide him and make him firm on the religion. Indeed, the supplication of the parent is answered as stated in the Sunnah.
Continue to guide him in a gentle and soft manner and clarify to him the virtues and good traits of Islam, and the benefits of acts of worship and obedience and their impact on the soul as they render it tranquil and comforted.
Also, you should be keen on linking him to Islamic centers and other institutions that have good programs that satisfy his needs, where he can partake in permissible sports and entertainment, and that teach him his religion. What is meant is that you should look for a good environment for him that will help him in good education and nurturing. If you don’t find any other alternative than migrating with him to a Muslim country, then do so.
Your participation with him in some permissible games may have a good effect on him, and a reason for him to accept what you say to him. Therefore, it is acceptable to undertake this course of action. Additionally, you can go out with him to public places, such as parks for instance.
For more benefit that the child follows the parent who is best in religion, please refer to Fatwa 122701.
Allah knows best.