Try to identify mistakes you're doing on your own first. Compare your sparring with that bag to fighters/bag work on youtube. You're very heavy on your feet with little to no head movement/footwork/hand defense. Your punches are all slow and use body weight instead of explosion/hips. A lot of the intricacies you're missing are not something that can be easily corrected on a forum. For starters I would get a real bag that has resistance and work on angles/footwork/combinations. Slow 1 / 2 punch combos won't progress you much. A big piece of advice is as you throw your job touch your temple with your index finger. Every time you throw your jab you're dropping your right hand, which is asking for major problems. Likewise, when you throw your right bring your left to your temple or at least jaw. Try utilizing some retreat footwork as well, your footwork patterns are completely impractical in a real spar.