As an amateur first-time exhibitor, you should be exploring venues close to your home that are willing to share your art with the public for free. There are lots of ways to locate such situations!
What organizations near you have display space in their buildings that change items periodically? Check with the library, the YMCA, any recreation centers or hobby stores that might have areas where you could display your work. If there are art stores or studios for artists in your area, ask the coordinators or managers of those facilities for suggestions.
Check with the art teacher at your school; ask for input from art galleries close to where you live. Contact the art department of a college or university in your state and ask them for suggestions. Is there an art display connected with a county fair or state fair where you live? Do you know anyone who works in an area that is related to the type of art you do - a graphic designer, sculptor, painter? Ask if they have any ideas or contacts.