I made a steel sculpture in high school a few years old and now,it has rust on it. So,is there anything I can do?
wire brush unless it’s fragile. If it isn’t fragile a wire brush on an angle grinder can save you elbow grease.
You can use something like rust oleum on it or floor wax to slow down rusting again.
If you prefer it being black you can heat it to cherry red with a welding torch which should lead to the formation of black iron oxide on the surface of the steel which will prevent red iron oxide from forming.