I answered that you can use the merge button under the alignment tools on the Homepage. The interviewer said I was incorrect. Then I described that you can also use a formula that goes =A2&""&B2 with the two cell references being the cells you want to merge into a new cell. That was also wrong, turns out they were looking specifically for an answer for the CONCAT formula which is also technically correct but the other two answers would achieve similar results. My recommendation to the hiring team would be to rephrase the question and make it clear that you are looking for a formula. Also its worth noting that the interviewer seemed confused by the examples that I presented and didn't realize they would achieve the same thing.