Congratulations.If you're cleared by your medical doctor for surgery, and I see no reason why you would not be able to proceed with breast augmentation surgery.
There is no problem with having breast augmentation after you have defeated thyroid cancer. Celebrate your victory over your cancer and have your augmentation.
If your medical doctor clears you for surgery, it should be safe. Please discuss this with your medical doctor first, and then find a board certified plastic surgeon to discuss all your options.
Yes, it is likely that you will be able to proceed, assuming your thyroid hormone levels are well-controlled. Of course, the physicians who know you best will be your best resource when it comes to specific recommendations. My best suggestion: select your plastic surgeon carefully and communicate your goals carefully as well. Best wishes.