Is this correct?

I just want to know if this paragraph is right, and it doesn't contain grammatical errors. Thank you for the answer!

"I brought with me this biscuit, banana and chocolate, which characterize my current eating habbit. In the exam period students think that they don't have time to waist. They avoid cooking and they chose the easiest way, I mean eating in the nearest fast food. I think healthy eating can improve the “biochemical prosess” of learning. So I try to compensate, (to counterweight?) the unhealthy fast foods with fruits like bana apple and orange. The biscuit is for breakfast. And chocolate is my special brain booster. So I’d like to give you this little present with which, I wish you a healthy and merry Christmas."