For your ENT TECH course, and probably others, you will need to use lots of images and videos in your assignments. Because of copyright laws, you should be aware of who are the creators of material you incorporate and how they allow their work to be used. There are special copyright exceptions for material used for educational purposes called "fair use", but it is still wise to understand usage guidelines. To be on the safe side, you can make a habit of only using "copyright-free" media.
Below are some excellent sites for locating free use materials and search instructions for using Google Images advanced features.