Data Analysis ANOVA

I am running an ANOVA analysis on my survey data. The survey has twenty total questions. I exported the file from Qualtrics to CSV first then opened it in Excel for Mac (Ver. 16.64). I noticed that ten people out of the total sample of 200 people did not complete the survey, leaving out an answer to one question. In the Excel file, these cells are blank. The rest of the other cells have numbers in them representing the survey scale, 1 to 4. When I try to run an analysis like ANOVA or any others, I get a message that says Excel cannot run the analysis because the blank cells have non numeric data in them. How can I fix this without deleting these entire records? I would like to keep the ten incomplete survey files especially because they only did not answer one question out of twenty.