It looks like a Link embedded in a Link
MOSFET works similar to NPN (2N2222).Arduino drives a voltage into the Gate thru 150 ohm resistor, (like R1),Source connects to Gnd,Drain connects to the 'bottom' of the motor.Rds of the MOSFET is very low, so the motor will see almost all of the battery voltage, vs the NPN wasting 0.7V across the Collector-emitter.
is there any alternative MOSFET to IRL? i would have to import it, and takes to long lol
Check the MOSFET which you already have, you need a switching mosfet, in data sheet look for threshold voltage less than 5V.example - IRF540Gate-Source Threshold Voltage VGS(th) VDS = VGS, ID = 250 μA 2.0 - 4.0 V https://www.vishay.com/docs/91021/91021.pdf
which transistor you are testing ?
Start with this
Make this work then go to next step
...in data sheet look for threshold voltage less than 5V.