How to ask in Chinese: What do you want to come to talk to me about? 你想去对我说 means you want to go to speak to me.
How to ask a question: What do you want to come to talk to me about? I don't know where to put the word 什么.
Is 你想去对我说什么 correct?
How to say a normal sentence (not a question): This is what I want to go to speak to you.
Is 這就是 我想去对你说什么 correct?
How to ask a question: Is this what you want to come to speak to me?
O'Connor sounds Irish: maybe you only speak Gaelic?
Perhaps you mean:
What do you want to speak to me about?
你想跟我说什么？
你想跟我聊什么？