Classify sentences containing typos into groups
If I understand correctly, you're looking for string similarity. There are several techniques available, the most simple is "edit distance" (aka levenshtein distance), which is the count of the minimum insertion/deletion/substitution/transposition operations needed to get from one string to the other.

For your particular task, I suspect "jaro-winkler similarity" would be better. JW is similar to ED, but was specifically designed for "entity resolution" (i.e. "record linkage"), which it looks like is what you're trying to accomplish. You can see a short demonstration of how this would work here