Theoretically, it is difficult to correct the age of 19. Surgery is a relatively direct method, but it will be obviously improved through long-term exercise, at least 1 year. I recommend you to search online for the "eight-step method" of O-leg correction invented by Japanese experts. There is also sitting in a chair, holding a thick book with your calf and doing the telescopic movement of your calf. Form a figure of eight on each toe with a distance of 15 to 20cm. After a slight squat, knees together, hands akimbo, do a squat.
At the same time, it is also good to buy an O-shaped leg to correct the soles of your feet.
Long-term persistence will improve. I hope it helps you.