how to merge footer cells or make a footer cell larger?

Excel does not support merging cells only in a special “footer” area of the worksheet. Any merging must be done on normal worksheet cells.

To make a footer-like area with larger cells at the bottom of the sheet:

1. Scroll to the rows you want to use as a footer (for example, rows 100–102).
2. Select the cells you want to combine (they must be adjacent in the same row or column).
3. On the Home tab, select Merge & Center > Merge Cells.
   • On Excel for the web: Home > Merge & Center > Merge Cells.
   • On Excel for Windows/Mac: Home > Merge & Center, then choose Merge Cells or Merge Across as needed.
4. Adjust row height to make the merged “footer” cell larger: right‑click the row number, choose Row Height, and increase the value.

If the cells already contain data, remember that when merging, only the content of the upper‑left cell is kept; all other cell contents in the merge range are deleted. Copy any important data elsewhere before merging.

To undo a merge, select the merged cell and choose Merge & Center > Unmerge Cells.

References:

• Merge and unmerge cells in Excel