It depends on the office.
To give you an idea, I have sold glasses, fitted them to patients, ordered them, done insurance forms, cleaned and stocked the frames, learned about all the types of lenses, taught people to wear contacts, done pre-screening like patient history and concerns, pupils, color vision, stereopsis, pressures with a handheld tonometer, kerotometry, cover tests, autorefraction, refractions with a phoropter, put drops in, triage patients on the phone, help the doctor when removing a foreign body in someone's eye, schedule appointments, clean the office, also worked with a retinal specialist and set up injections, lasers, cryotherapy, etc. It is a lot of repetition. Take a patient and do the pre-screening then the next patient, then the next patient.
Is it hard work? Not like dairy farming. Do days get long? Yeah, especially when you yourself are having a bad day but you have to keep a smile on your face and be polite to every patient you talk to. Some patients are super nice while others just want to ruin your day. Overall, it is enjoyable. The doctors I have worked for have always want to teach me what is going on and more about diseases, etc.
I'd say you should get a job as a tech if possible. It'll really help you understand what happens in an eye care center, and it will expose you to some interesting things. Plus, it is usually higher than minimum wage.
Hope that helped.