Lets on start with easy stuff but jump right into the big questions about Christianity, I’ll do my best and get people to help me with this. First the holy Trinity, it is he Father, Son, and Holy Spirit in one. The Father is God, Son is Jesus and Holy Spirit is Jesus after the resurrection. They are all the same thing just not really…..this is where it gets confusing and most Christians have trouble understanding it. Many people say that it is the mystery of the trinity but this is not so. A "mystery" is not something we can know nothing about; it is something which we know but can never entirely comprehend. Thus everything having to do with our Infinite Creator is a mystery, for the depths of God are ultimately incomprehensible. Yet we do know something about God, for God has revealed Himself to us. And one thing God has revealed is that there are Three Persons in the Godhead. The best way to say this w/o making a contradiction would be that there are Three Persons in one God, meaning that the Three Persons share one and the same Divine Nature. Are you confused yet because I’m starting to confuse myself, but first I need to explain Person and Nature to you. The words person and nature describe two different things. Person denotes who someone is, while nature denotes what one is. So if we ask "Who is God?", the answer is "God is Three Persons: Father, Son and Holy Spirit". If we ask "What is God?" the answer is "God is One - a Single Divine Nature". If we put these two truths together we find that God is Three Divine Persons who share one Divine Nature. (having a dictionary on your computer is really helpful!) I might have contradicted myself some where and if I did sorry, tried not to but with this issue one must choose their words carefully. But this should help clear things up a little bit.
Now I’m going to get a little anger towards your next statement about having “trouble believing in the trinity because there is no solid proof of it in the bible.” Of course there is no solid proof, the trinity is a concept not a tangible item like the triforce (though it was a good example). But if you understood what I said above Jesus had the same mind as God and the Holy Spirit, and Jesus was solid. People saw the Holy Spirit, and since it was a spirit one could not touch if, even thought Jesus told Mary no to touch him after the resurrection. God himself is not tangible but everything he made is (to an extent) but going by your logic you mush have trouble believing in God since he was never solid. Ah it’s all so maddening but do you get it?
I will get to the other two subjects later, right now I gtget to class, hope this did help some and if not tell me why and I will see what I can do.