build and understand this for starters, it is everything you need in miniature:
https://itp.nyu.edu/physcomp/labs/mo...th-an-arduino/
Eventually you will probably use the transistor to switch a larger transistor, and have to deal with gate currents and whatnot, but this is the basics, including microcontroller programming.
Or delegate it to someone in EE, or spend $30 on ebay for a chinese controller.
Edit, I was stuck on 750watt, you aren't serious about putting that in a car (and are a senior in ME) I hope.