Although I am 12 years old, I do enjoy learning physics. However, sometimes their is a common issue when I look up something like " Introduction to Gauge Field Theory": whenever I read the document, their is some complicated math stuff that I don't understand. Here's an example: I really need help with math like this. I can't understand physics without it. So my question is: What type of math is this? Where can I learn how to do it and understand it? Is their any specific thing I should study? Any website or book?