SAP allows users to enter data in the following ways:
Insert: Data to the right of the cursor moves to the right as you type.
Overwrite: Allows you to type over data to the right of the cursor.
The right side of the status bar shows which mode is currently active with the abbreviation INS for Insert or OVR for Overwrite.
You can toggle from one mode to the other by clicking on the INSERT key, or on INS
or OVR on the lower right of the status bar to switch to the other mode.
If you do not see the INS or OVR options in the lower right corner of your screen your status bar may hidden.
You can expand the status bar to see these options by clicking on the arrows on the right side.
This will result in the INS or OVR options becoming visible on the right side of the status bar as in the first two screenshots above.