In order to locate an applicant's assessment score, you first need to find the applicant. If you can't find them by using the filters at the top of your Applicants page, try searching for them by name:
More info: Help! I can't find an applicant.
If you can find an applicant but cannot find their assessment score, check their Assessment hiring step, wherever it may be in your hiring workflow. Click the number next to the name of the assessment to view the full score report:
Here's a video about finding and interpreting both assessment scores and prescreen scores:
If an applicant is missing a score or only has one score, check out this article for further troubleshooting: Troubleshooting Assessments.