[heurist]

As others have mentioned, the important thing is to start. Build something and get it in front of potential customers, figure out what is wrong about it and revise. But these helped me as I built a SaaS startup over the last few years:

Obviously Awesome: How to Nail Product Positioning so Customers Get It, Buy It, Love It https://www.amazon.com/dp/B07PPW5V9C/ref=cm_sw_em_r_mt_dp_U_...

The Challenger Sale: Taking Control of the Customer Conversation https://www.amazon.com/dp/B07SLDD5YV/ref=cm_sw_em_r_mt_dp_U_...

Deep Work: Rules for Focused Success in a Distracted World https://www.amazon.com/dp/B0189PVAWY/ref=cm_sw_em_r_mt_dp_U_...

Who: The A Method for Hiring https://www.amazon.com/dp/B001H97LVO/ref=cm_sw_em_r_mt_dp_U_...

The Brain Audit: Why Customers Buy (And Why They Don't) https://www.amazon.com/dp/B0149NJXMO/ref=cm_sw_em_r_mt_dp_U_...

I have more recommendations as well but they might just be distractions until you get started.