A collar bone fracture usually heals within 6 weeks. So, you can go ahead and start the training program you want to. But, there is also a word of caution. Fractures can be notorious and can raise unwanted pains at odd times when under strain. I would suggest you get the muscle power and shoulder movements of both your shoulders checked by a physiotherapist and only when the muscle power of both your shoulders is same, should you start your training.