One of the easiest ways to make red velvet cake at home is to buy a red velvet cake mix and make that up at home. This also saves you the time that you would spend actually making a cake mix, reducing it to simply adding eggs, water, oil, and maybe some butter to the boxed mix (read the directions!) and then baking it.
However, if you really want to make red velvet cake at home, there are plenty of recipes online that you can follow for red velvet cake. It’s basically a chocolate cake with red food coloring. The red food coloring is what gives red velvet cake the dark red color that it’s known for, and leaves the cake richer than if it were simply a chocolate cake.