The L298 is not a great choice for a battery powered motor driver. The driver itself drops 2 to 4 Volts (depends on current draw). At 1 Amp current and a drop of 2 Volts that is 2 Watts wasted as heat. You don't say what type of motor that you are driving, but Pololu has modern MOSFET output drivers for steppers and brushed motors that are much more efficient.
I'm going to drive my Plane's engine. It's from a drone. I dont know what is pololu and is it avaiable in Turkey. Plane is OK now . But I dont sure about it can fly. If I use "pololu" is it run faster ? And In the plastic case of engine it have a gear. It slows the propeller. How can I disconnect the gear from here ?