open a file
vim 文件名
edit
Then use the up and down arrow keys to adjust to the position that needs to be modified, and press the "i" or "insert" key at the cursor to start the modification operation.
Save and exit
After the modification is completed, click the Esc key to enter the command prompt line and start the save operation. After the bottom INSERT disappears, you can enter: wq to save the operation.
Activation file
source 文件名