The easy way is often the wrong way. You might be copying more than you think. It's so fast and simple that it is easy to lose track of the author. Helping you do the work can easily slide into doing the work for you. And when you help others, you may find it's easier or faster to just do it for them.
Most students are more or less honest and fully human.
They screw up when they are up against a wall. But plagiarism is a very bad solution to very common problems. Here are some better solutions to try. Get explanations, suggestions. Make sure you understand exactly what is expected on the assignment.