If you want to add complex numbers together, first regroup them so that like terms are next to one another. Then, add the like terms together, and you have your answer! To see an example, check out this tutorial.
When you subtract complex numbers, you first need to distribute in the minus sign into the second complex number. Then, regroup the terms so like terms are next to each other. Combine those like terms, and you have the answer! Watch this tutorial to see a great example!