Switching between different frame

I mentioned earlier that there is a need to switch between different window, so what about different frame? It also needs to be switched. I saw a lot of friends' posts saying that the page object could not be found. Only after the survey did I know that the website used a lot of frame. Although individuals usually encountered very little, and I was very disgusted with the structure of such a website, I still had to solve it. I wrote a super simple multi-frame page by hand, and debugged it by the way. In summary, I encountered multi-frame. A common step may be: first switch to the frame you want, then switch to the main frame after the operation is over, and then switch to other frame you want. For the frame source file, see attachment:

Unexpectedly, I can't even pass the attachment.

Does it have to be in zip format?

Attachment: http://down.51cto.com/data/2364538