The usual starter line, if Im not in the right place let me know but heres the story:

Ive got a model boat wired up with a raspberry pi(Experimenting with python I'm aware there's better options haha), wired up to two regular DC motors. Now I feel like I'm missing something simple here, probably just blind from staring at the thing too much, but I cant figure out how to calculate the differential steering at all. I'm completely clueless. admittedly calculations arent my strong suit, this is just a hobby for me.

So basically, I have an initial thrust value of 0-100 and a steering value of -1 to 1. -1 on steering being left. Reversing will come later, first I gotta move at all

So what I've got to figure out is what the right motor PWM and left PWM is for any given value of the two variables.

As I said, its a hobby, I may be doing something stupid or ridiculous here so let me know, I'm beginning to doubt if python really is the best choice and I'm thinking of migrating over to c++. Either way though if anyone can give some advice or even just point me in the right direction to figure out the problem it would be very much appreciated.