Excel provides three ways to merge cells, which one by one described below.
Merge and Center
To merge a group of cells and center the text, you can also use the Merge and Center as below image.
Now enter some text into merged cell and see output as below image.
To merge a group of cells and across the text, you can use the Merge Across optionand see the output as below image. If you want to enter text into center then first select Merge and Center option then select Merge Across option.
You want to display text into left-hand-side, not centered then select Merge Cell option in place of Merge & Center option as following image.