In Excel, a person can type in information in each cell. Then the person can sort the information. Also, instead of inputting data into each square, the person can see if there is a pattern among the data. Then the person can put a formula into a cell and designate which cells should the formula apply to.
The data would then be entered into those designated cells based on the formula. Then a person can highlight a group of cells. To do this, the person will need to hold down the mouse button while moving the cursor or mouse over the cells. This group of cells that form either a square or rectangle is called a range. Then you can bold or do other things to that range of cells.