To merge cells using the "Merge & Center" command:

1. Select the range of cells you want to merge. For example, choose cells A1:F1.
   
   
   
2. Click the "Merge & Center" button on the Home tab. This will merge the selected cells and center the text inside.
   
   
   

If you want more merge options:

1. Click the drop-down arrow next to the "Merge & Center" button on the Home tab. This opens the merge options menu.
   
   
   

There are several options here:

• Merge & Center: Merges the selected cells and centers the text.
• Merge Across: Merges the selected cells but keeps each row separate.
• Merge Cells: Merges the selected cells without centering the text.
• Unmerge Cells: Unmerges any selected cells.

Be careful when using this feature. If you merge multiple cells that contain data, only the content from the top-left cell will remain. All other data will be deleted.

Alternative: Center Across Selection

Merging cells can cause issues later, such as difficulty when moving or copying content. A better option is to use "Center Across Selection." It gives a similar look without actually merging the cells.

To use "Center Across Selection":

1. Select the range of cells, like A1:F1. If these cells are already merged, unmerge them first.
2. Click the small arrow in the bottom-right corner of the Alignment group on the Home tab.
   
   
   
3. A dialog box will appear. From the "Horizontal" drop-down menu, select "Center Across Selection," then click OK.
   
   
   

This will center the text across the cells without merging them. The result looks the same as merging and centering, but it keeps each cell separate.