Don't worry about too many details, and don't let it bother you that you won't understand everything right away. Just get connected to a mud and start to have fun. Later, as you are more experienced, you can spend some time exploring the various features of your mud client. However, muds vary enormously, and I encourage you to visit several muds until you find one you like. No matter what your interests and inclinations, there is a mud out there somewhere for you.
Some muds are purely for talking.
If you want help deciding which type of mud to try, here is a Web site that can help you. Personality-based Mud Recommendations The Zhing Mud I sponsor a mud called Zhing, and I invite you to visit it. Zhing was planned and developed by a group of people who have years of mudding experience. These people have created a rich and engaging environment based on a medieval fantasy theme with a well-developed mythos. As with all adventure muds, you can spend time talking with other people, as well as exploring.