The entry of "Buddhist qigong" says: "Buddhist qigong originated from Buddhism, and some of it is circulated among the people, and its martial arts cannot be equated with religious belief." It can be seen that in terms of its Buddhist essence, Buddhist Qigong is a heresy attached to Buddhism. As a disciple of Buddha, since he believed in Buddhism and accepted Sanzang's conversion, it was equivalent to returning to the enlightenment of Sambo. There should be only one purpose for Buddhist disciples to return to the Sambo, and that is to free themselves from the cycle of life and death. The three treasures of Buddhism, Dharma and Monks can give life support and liberation to Buddhist disciples, but Buddhist Qigong can't. Therefore, fundamentally speaking, it is best for Buddhist disciples not to practice Qigong, but to learn from Buddhism and practice Qigong, which shows that their beliefs are not pure.
However, Qigong is a kind of physical exercise and a part of China traditional culture. If you are engaged in sports research or want to understand the traditional culture of China, you can learn Qigong, because you don't want to rely on Qigong to solve the problem of life and death, but just regard it as a part of the world law. Similarly, if you want to learn qigong performance in order to earn money to support your family, it is not bad to learn it. If you just want to study as a physical exercise, it seems unnecessary. There is a saying that "Buddha worship is the best physical exercise" is reasonable. If you just want to exercise, you can try to worship Buddha more first.
See what you mean by taking Qigong as a fitness exercise. If that's the case, I think it's ok, but I don't think it's necessary to practice qigong after practice. If you think you can handle it, you can try, but you'd better ask your guru, or keep in touch with your guru at any time if you have any questions in the process of practicing Qigong. Remember that he is only a tool for your fitness, and it is absolutely impossible to achieve the purpose of life and death.