Is miner and minor similar

The nouns 'miner' and 'minor' are not opposite and do not have the same meaning.

The noun 'miner' is a Word for a person who works in a mine.
The noun 'minor' is a Word for a person a person under the age of legal responsibility; a Word for a secondary area of specialized academic study.

The Word 'minor' is also a verb and an adjective.