You could use an index concordance file. No code required. See: https://www.dummies.com/software/mic...cordance-file/.

The Index concordance document is essentially a two-column table in which the texts to be indexed are in the first column and the form of the Index entries are in the second column. Done properly, the process is effective, straightforward, and efficient.

See also: https://answers.microsoft.com/en-us/...5-418fc592862b