I have an enlarge thyroid gland no cancer, med size gowing slowly doctor wants to operate before it is to large 63 years.

Get tested. ultrasound, nuclear thyroid scsn with uptake, blood tests: TSH, T3, (liothyronine) T4 FTI and anti-thyroid antibodies. Surgery should be a last resort if you are having compression symptoms from the enlarged thyroid.
Thyromegaly. Cause of thyromegaly should be identified. Usually Thyroidectomy is indicated for CA or symptoms of thyromegaly.
Goiter. If goiter is pressing on your other organs like Esophagus and causing swallowing difficulty, or on Trachea and breathing difficulty or big enough to cause significant disfigurement or not responding to medical treatment your doctor may recommend to remove it partially at least.