Hello, if you use your relative’s patent to write a plan, you need to obtain his consent in advance.
The business plan recommends that you analyze it from both subjective and objective aspects. The objective is the general market environment, as well as the surrounding consumer groups and purchasing power. The subjective aspect is the operability of the project itself, its development prospects and its competitive advantages. Furthermore, there are problems that may arise during the project and how to better avoid risks.
I hope it will be helpful to you and I hope you will adopt it. I wish you good luck!