Can you have withdrawals from trazodone 150 mg if u have taken it for 9 months? If so what's best way to taped I'm taking ambien (zolpidem) now too

Taper slowly. Best to discuss a plan with your doctor. Sudden cessation not a good idea, and slow taper over several weeks seems a far better approach.
Yes. You can get rebound insomnia. I recommend going down to 1/2 for now week than stop.