I get confused really easily?

okay, im not dumb or mentally retarded or anything, and of course sometimes i can be "slow" and have those "dumb blonde moments", but during school i sometimes get so confused on what to do and even sometimes wen someone explains an ignment to me i still don't fully comprehend. i get nervous on if this or that is the right way to do the project, or i just get confused. sometimes, i need to ask the teacher or someone over and over again, but of course of i don't b/c i don't wnat to annoy them. being unsure and confused sometimes really frustrates me deeply, especially on important projects. is there any way to not get so confused or unsure on what to do so i can get on with my work? i dont know what's wrong with me, and i wish i could just have something click into my brain when it is told to me. i know i can be a little dense, but its really annoying. it is kind of hard to explain, but i hope someone knows what i mean! help, please?