The generator light should go off once the engine starts. If not it could be an easy fix like a bad ground. I recently had my starter generator fixed after it was making a squealing noise. I've been very busy lately so I took it to a local automotive electric repair shop. He replaced the bearings, brushes, armature and an end cap. He said it spun a bearing and the armature was grinding away inside the starter generator. He showed me the old parts and it was bad. It was done in a day which I was happy about but a bit pricey. It now is very quiet and working fine.
Keep the Peace ✌
Harry