Here is a set of 12 videos, by Dr. R.C. Sproul, teaching the basics of Reformed Theology. I highly recommend this video series! Dr. Sproul was a gifted communicator, and conveyor of Reformed theology.
Also, if you’re looking for a book, I highly recommend this one, which has the same name as the video series. It’s probably the best modern book to introduce Reformed theology to someone who knows very little about it.