Similarity calculation between sentences (strings) of a same row of two columns

Hello

I am trying to measure the similarity/distance (Levensthein, Cosine and Jaro Winkler) between two sentences of different columns of each row, but I can’t do it. The Similarity search does not work for me because it looks for the most similar texts and what I want is to measure the similarity between two sentences. I have seen similar examples, but none that fits my requirement. Any clue?

Thanks