Before you can earn a master's degree, you need to earn a bachelor's degree. A bachelor's degree is a 4-year program of study in a particular field, from English to Astronomy. Earn your bachelor's degree at a local college or university, or online through a variety of programs. Once you have finished your bachelor's degree, you can begin to pursue a master's degree.
Some master's degree programs will require you to take the GRE, which stands for Graduate Requisite Exam, before you can enter into the program. The GRE is a test of general knowledge that is often used as a prerequisite for entrance into graduate programs. Take the GRE at a testing center in your area; the test is computer-based and will take a few hours of your time.
Some graduate degree programs may require a specific GPA (grade point average) from your bachelor's degree in order to admit you into their master's degree program. Check with the programs you are interested in pursuing to identify their grade requirements before pursuing your degree.