There is a lot of trash in the Internet related to electric motor design. And even more when it comes to magnetic coil calculation.

This site: is the best calculator I could have imagined. Contains field calculation at a given distance, inductance at given frequency, estimates power dissipation, wire length and total impedance

This site: is the best visualisation of winding scheme for given poles and stator slots number

And this article is the best explaination of BLDC _s_p configuration