The pycharm program interface generally has many sub-windows, as shown in Figure 1.
Figure 1 Pycharm child window
If you find that some subwindows are missing, Figure 2 is the most extreme case, don't worry.
Figure 2 The child window of the Pycharm interface is gone
Open the Project View subwindow
Selecting the menu "View > Tool Windows > Project" opens the project view sub-window on the left. As shown in Figure 4
Figure 4 Open the Project View sub-window
Open the run subwindow
To open the run window at the bottom, move the mouse to the icon (like a small window) in the lower left corner, as shown in Figure 5.
Figure 5 Move the mouse to the icon in the lower left corner
Then select the Run menu item, and the Run sub-window will appear.
There are other subwindows, such as "Python Console" (that is, the Python terminal), "Terminal" (that is, the Windows terminal), which you can open in a similar way.