When should an undergraduate attend their first professional academic conference if they have nothing to present and traveling isn't cheap? Would while enrolling for a masters degree be a better time? I'm thinking American Stat Association.
Ask one of your professors who attends the conference about this. Ask what you could gain. If the prof is actually going, maybe they could shepherd you around so that you could meet people.
I don't know about the conference, but see if they have things for students, especially such things as a doctoral symposium where you can hear about student work in progress, even if it is a bit beyond where you are.
Aside from the standard program, conferences are a good way to meet people, though for an undergraduate the first one might not be so valuable unless you have a guide.
But long term, building a circle of like minded people, especially potential collaborators, is a major benefit.