B2B SaaS is a very large field of human endeavor. If you're looking for an entry point, I wrote one, but the field is multifaceted and I have no recommendation or set of recommendation that covers every facet.

I will say that producing beats consuming in business and that many people have a tendency to hoard great information about B2B SaaS businesses without talking to potential customers, selling SaaS, or coding SaaS, but that collecting guides/interviews/etc has built precisely zero SaaS companies and talking/selling/coding has created many.