Praise be to Allaah.
There is no blessing in this world like embracing Islam, and there is no misfortune, sin or tribulation in this world like staying in kufr (disbelief). The created being must enter the religion of the Creator, and not wish for any other religion except Islam. The Creator knows the situation of His creatures and understands their inabilities, weaknesses, forgetfulness and mistakes, and so He forgives us for mistakes that are made unintentionally. Allaah does not ask anyone to do anything that is beyond his abilities, as he says (interpretation of the meaning): Allaah burdens not a person beyond his scope [al-Baqarah 2:286]. The Prophet (peace and blessings of Allaah be upon him) said: Allaah will forgive my ummah for their mistakes, and for what they forget, and for what they are forced to do.(Reported by Ibn Maajah, 2033; see also Saheeh al-Jaami, 1731).
What you have mentioned in your question that you may eat something haraam without realizing is not something for which you will be punished. As long as you are going to do your best to avoid what Allaah has prohibited which is what you have indicated in your question then there is no sin on you. Even if a person does commit a haraam deed, Islam still offers a way out from every sin, in the form of repentance, remorse, determination not to repeat the sin, and seeking forgiveness from Allaah. This guarantees that the sin will be erased. So go ahead with determination, and do not hesitate. Allaah will be with you and will not let you down so long as you are following the religion with which He is pleased. May Allaah help you and keep you on the Straight Path. May Allaah bless our Prophet Muhammad..