Minimal pairs are two words that are pronounced almost in the same way, but they have one sound that makes them different. The sound can be a vowel or a consonant.
These pairs have nothing to do with spelling or meaning. The words>sound similar but they do not mean the same thing. Their definitions have nothing to do with each other.
They might be spelled very differently, but the actual sounds will be quite similar. Or, the two words in a minimal pair might be spelled very similarly, with just one different letter.
Minimal pairs often confuse English learners. Many English learners will replace one word with another while speaking. This completely changes the meaning of the actual sentence.
However, if you learn minimal pairs, Practicing minimal pairs is a great way to become a better English listener.