vim--open multiple files, display multiple files at the same time, switch between files

To open multiple files:
1.vim has not started yet:
Enter in terminal
Vim file1 file2 ... filen can open all the files you want to open
2.vim has started
Input
: Open File
A file can be opened again, and the contents of the file will be displayed in Vim at this time.

Display multiple files at the same time:
: Split
: Vsplit

To switch between files:
1. Inter-file switching
ctrl+6-Next file
: bn-Next file
: bp-Previous file
For files opened in multiple panes with (v) Split, this method only switches different files in the current pane.
2. How to switch between panes
ctrl+w+ arrow Key--Switch to front/bottom/up/back one pane
ctrl+w+h/j/k/l--Ibid.
ctrl+ww--Switch back to the next pane in turn

vim--open multiple files, display multiple files at the same time, switch between files