You got the right parts.
When the uP output is low, the LED in the opto is off. This puts the photoxistor in the dark which means it has a very high resistance. That means the collector (output) of the PT is high. A high input to the gate driver will be inverted, making its output and the gate of the FET low.
When the uP output is low, the LED in the opto is off. This puts the photoxistor in the dark which means it has a very high resistance. That means the collector (output) of the PT is high. A high input to the gate driver will be inverted, making its output and the gate of the FET low.