How do you practice Qigong exercises?
This is a great question, and there are many schools of thought. Myself I would learn the exercise physical movement first, then learn and visualise where the energy comes from and direction it moves in the body.
The next step would be to visualise which meridian the energy is travelling in and its direction. This is on a higher level of qigong practice and it requires knowledge of the meridian location and pathways and interconnection with other meridians.
So, before all of that I would start learning how to move the body gently and quietly and learn how to relax. Then learn how to keep your mind in your body. Note: This could take you a few years of practice.
Know that it’s a life time practice, and you have plenty of time.