Press the Del key.
The 'F2' key will select the active cell and move the cursor to the end. You could also double click a cell and then press the 'End' key.
active cell
active cell
If the cell is selected then it would be called the active cell. In practice, every cell is ready for data entry, so on that basis there is no special name for them. To put data into a cell, it must be selected and it then becomes the active cell.
It is the active cell.
active cell
If you press the Delete key, it will remove the data, but the formatting will remain, such as the colour or fonts or numeric format. When you type another similar piece of data in, it will apply the formatting to it.
Active cell
There are lots of ways, but the easiest is to press the Delete key.
press reset
Active cell
press ESC