The fastest and easiest way to combine two or more cells in Excel is to use the built-in Merge and Center option. The whole process takes only 2 quick steps:

Select the contiguous cells you want to combine.
On the Home tab Alignment group, click the Merge & Center
Once you click Merge and Center, the selected cells will be combined into one cell and the text is centered
Other merging options in Excel
To access a couple more merge options provided by Excel, click the little drop-down arrow next to the Merge & Center button and choose the option you want from the drop-down menu:

I hope this helps!
Tim Paine