If you want to practice, I suggest you practice the health-keeping exercises of pure health-keeping departments such as Wuqinxi, Baduanjin or Yijinjing. Search on video websites. There are tutorials. At the beginning, I started doing these fitness exercises by myself.
If you want to fight in actual combat, you are still a student. You learn Xingyiquan by yourself, and you are one of the Tai Ji Chuan (you have to practice Gong Zhuang when practicing routines, for example, three postures are good things, and if you can stand for half an hour for the first time, I think you are awesome). You have to have a certain understanding ability and practical spirit to understand internal strength, and so does Gong Zhuang Baidu. Anyway, practicing boxing and hitting piles ensures that you are strong when you are not a student.
By the way, if you are really in poor health, practice Wu Qin Opera. Generally, if you practice Ba Duan Jin, you want to practice Yijinjing. There is not much time, at least ten minutes a day. If you practice three times a day according to the standard, it will take 40 to 50 minutes. You must experience the process yourself.
PS: Don't be too full before and after practice. Drink water before practice in the morning, don't blow it during practice, don't blow the air conditioner, and don't eat or drink water immediately after practice. At least, at least, you should calm down your qi and blood. You said there was not enough time to practice internal boxing. After all, a few hours a day is not effective, but if you want to strengthen your muscles, you can stand on a stake (type 3) and keep breathing. Oh, it's not negotiable whether the early stage is good or not. If you have money, you'd better eat more nutritious food, such as walnuts, honey, bean products and carrots.
Say so much first, and then ask if you don't understand.