You have 2 lists, but the 2nd list contains duplicates from the 1st, so naturally you’d want to remove them. In LibreOffice Calc you can do that via the Filter tool.
In practice this can be useful if you want to isolate emails you’ve already sent messages to, or products you’ve published.
For bigger databases you should put focus on software like LibreOffice Base but if you want to do simple operations without digging deep into the rabbit hole of skills and confusion, just use this easy operation on a basic spreadsheet.
Data > More Filters > Standard Filter
Field selection (has to be a single row) > = > Not Empty > Options > Range contains column labels > No duplication > Copy results to new row
Between the original values and the new ones, add a division of random symbols like ‘’’ or ////
Values under the division are not duplicates and are free for use. Select the entire row you wish to get non-duplicates from, otherwise you’ll have 1 wrong value.
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