On Thursday, 13 Aug 2020 at 13:33, Xianwen Chen (陈贤文) wrote:

I would like to receive tips regarding how to permanently set up the
window layout that I have on my mind. The layout has three windows.

Have a look at this variable which may provide what you want:

,----[ C-h v org-agenda-window-setup RET ]
| org-agenda-window-setup is a variable defined in ‘org-agenda.el’.
| Its value is ‘other-frame’
| Original value was ‘reorganize-frame’
|
|   You can customize this variable.
|
| Documentation:
| How the agenda buffer should be displayed.
| Possible values for this option are:
|
| current-window    Show agenda in the current window, keeping all other windows.
| other-window      Use ‘switch-to-buffer-other-window’ to display agenda.
| only-window       Show agenda, deleting all other windows.
| reorganize-frame Show only two windows on the current frame, the current
|                   window and the agenda.
| other-frame       Use ‘switch-to-buffer-other-frame’ to display agenda.
|                   Also, when exiting the agenda, kill that frame.
| See also the variable ‘org-agenda-restore-windows-after-quit’.
`----

I have a new frame popup when I ask for an agenda view, leaving the
window setup for the original frame untouched.