Conferences give you a chance to meet others in your field. These are people that you will be working with if you stay in the field.
Many conferences have special student rates. Or for some work, you may get free or reduced entrance.
Conferences also have special tracks for students. Sometimes they'll have poster sessions for students to provide the highlights of their work and to interact with other students and researchers. Students provide a summary of their work on posters or larger boards. They make also come supplied with cards to hand out or a sign-up sheet for people who are interested. Then the students remain near their posters at scheduled times to discuss their work -- sort of like a science fair. There may also be interactive demos. Among other purposes served by interacting with others in their fields, this gives students a chance to interest prospective employers.