As for the internship, it's hard to get in ... At least in the years when I had a meal at the stock exchange, the brokers I contacted rarely recruited pure interns directly. Those who came to the internship were either people who had already been hired, or they left after saying hello last week (the vast majority of existing brokers are state-owned enterprises at all levels). My brokerage company cooperates with a local university every year. The university will send some interns to stay for a few weeks, but they are also engaged in some low-tech jobs, such as sorting out materials, so it is good not to let you be a copier administrator. As for the securities qualification certificate, this is not a very important factor. Anyway, this certificate is not difficult to test.
Therefore, it is hard to say what conditions you need to practice. Even if you go in, you may only be engaged in some very elementary work for a short time. Undergraduate students who want to enter Huatai Securities can only work in the sales department. You can try your luck by calling several sales departments of Huatai Securities.
If you don't just plan to practice for a week or two, but are actually willing to engage in this line, you might as well apply directly. It's no problem to be a stockbroker. It's just a lot of pressure. After all, you are only an undergraduate, and your diploma has no advantage.