Mzbel, I am always happy when people ask questions about deity of Jesus Christ and try their best to seek for the truth. I do not side with Christians who say we are not supposed to question the Christian faith. I always tell people, our eternal life is so precious that we cannot afford to make the wrong decision whiles on earth now. It is, therefore, very important to question every faith to determine which is true and reasonable to put your trust in. Do not allow anyone to intimidate you on your quest to find out the truth. Ask all the questions you wish but be modest in your words. I will try my possible best to give reasonable answers to questions raised in your post.
In your post you stated, “Sorry to disappoint you but when I mention G-d, I mean "Hashem" the G-d of Israel, the only true G-d I know, not Jesus. I believe solely in the Torah (The Old Testament) because it is self-explanatory and accurate.”
Mzbel, I am glad to inform you that there is only one true God as the Shema states in Deut. 6:4 (also in 1 Cor 8:4 & Mk 12:29). He is the God of Adam, Abraham, Isaac, Jacob, Moses, Elijah and Elisha and so on. And is this same God that Christians worship. We do not worship any other God apart from Him. Christians believe the revelations about God in the Old Testament (OT), which manifested in the New Testament (NT), suggest that God is not a Person (Unitarian) but Three Persons (Trinitarian). Before I say anything, I wish to bring one thing to your attention that nobody on earth can explain God to you. God is extremely unexplainable, unimaginable, unthinkable, infinite and an indescribable being. Humans do not have the appropriate words to define or describe Him. An all knowing, all powerful, all loving, and an omniscience being should be extremely difficult to explain by any finite being. That is why it seems there is always some kind of confusion as to who is worshiping the true God. But in all things we should allow SCRIPTURES to speak to us and direct us as to what God has revealed to us about himself.
When a Christian calls God, he/she is referring to Three Persons (ie. The Father, The Son and The Holy Spirit). This is where the concept of the Trinity (Tri-unity: Three but One) came from. It is very interesting to know that, the blue prints of God (The Father, The Son and The Holy Spirit) are found at several places in the OT. Since you don’t believe the NT, I will not try to explain to you why the authors used the Greek names “Ha Theos” and “Ha Kyrios” to distinguish between God, the Father and God, The Son respectively. I believe by now you would have done some exegesis on some scriptures, suggesting God is not Unitarian. Some of these scriptures include Gen 1:26 and Gen 11:7 (where God used a plural pronoun ‘us’ to refer to himself). Some people think these scriptures are not strong enough to prove the Christian claim about the personhood of God being more than one.
In addition to those scriptures, Gen 19:24 reads “Then the LORD rained down burning sulfur on Sodom and Gomorrah--from the LORD out of the heavens”. This verse suggests that there were two LORDS, one in heaven and the other on earth and the Lord on earth commanded burning sulphur from the Lord above or in heaven.