If there a just the kind of typos that you show in the photo, easy to open that record and change the wrong letters to correct ones.
1. Correct everything that can be corrrected.
2. Click on that person's name so record opens in new screen. If it is a duplicate, there will be an up-arrow at upper right.
3. If you are sure the person is entered two times but don't get that arrow, compare both entries carefully. Any little difference and the code won't see it as a duplicate. Check the entries and try again.
4. If you need to delete an entire record, open it and create a copy of another correct entry, and then merge those two as duplicates. This is called a "fake merge'
Hope this helps.