Tourist L before Student X

No, you can only hold one visa at a time. If you will study here, a student X is ok, but keep in mind that you need to get a residence permit within 30 days after entry. That is to say, you have to register with your school as early as possible after entry to start this process. Once your application of residence permit is under processing, you can travel around if you like. Please check with your school first if they help with students who arrived earlier than scheduled term.