yes that is the Time that the BONE requires for Healing, If given Proper Nutrition and Rest. by rest it is Immobilization at that joint. But Also, a point to understand is that if you Do not move your Ankle(IMMOBILIZE) it for So Long, then there are quite good chances of shortening of Soft tissue (Skin, Muscles and Ligaments) . Also A good chances of Weakening of Muscle.
NOT TO WORRY Because that is Normal. Therefore you may have to go to a Physiotherapist Post 4-5 weeks and Start off with Gait Re-training and Kaboom by end you would be able to walk independently and comfortably. If you have Trouble Following your daily routines , please consult nearest Occupational Therapist.
Next Steps
Rest for NOW, EAT A HEALTHY DIET AND Join Physio later When Your Surgeon Advice you. Just have to Wait for Calus Formation.
Health Tips
EAT healthy and Do not take Tension, Enjoy Life and If you Are Having Trouble in Following your Daily Routine (bathing , Toileting, Grooming, Dressing, Working, Leisure etc..) NOW, YOU MAY Consult Occupational Therapist Right away. He / She would be able to Help you solve the Issues. STAY HEALTHY