I had to google those definitions first because I did not know what they mean.
So if anybody else has the same problem here the wikipedia definition:

Anarcho-capitalism is a political philosophy that advocates the elimination of the state in favor of individual sovereignty, private property, and open markets.

Minarchism is a libertarian political philosophy which advocates for a minimal state, that is, a state that acts only on very essential functions, while all other functions are provided by the free market.