A Study about Online Marketing tools

Great week to all! I really want to know if there is a certain field of study that relates or focuses only about digital online marketing. Actually, I already have a knowledge about business management. I took up that in college. I’m interested to consider online marketing for additional learning. I wonder if these smm, sem and seo tools can help us in our business. Or do I need them all to gain my site’s increase in popularity around the globe ? Maybe, I need an expert’s point of view here or pursue a study or seminar about it?