Be an optometrist, though. Do ophthalmologists have to do surgery for their practition?

NO. Ophthalmologists are medical doctors who specialize in the diagnosis and medical/surgical treatment of eye diseases. Optometrists are trained to diagnose and treat certain eye conditions with medication. Some ophthalmologists choose not to perform surgery; they are termed "medical ophthalmologists".
No. Optometrists can provide medical eye care but are not trained in surgical eye care. Ophthalmologists are trained in both but are not required to perform surgery to practice. Many general ophthalmologists do not perform surgery by choice.