I'd starting a consulting business, based on the fact it has to be my primary income. Can't afford to take much risks and do anything that has a much greater chance of failing.
The US is about to double it's onshore manufacturing capabilities as it bows out of the cold war role as the World's policeman. This means globalization is done.
All of that capacity has to be built, quickly, with less labor than ever before, with less money as well. Small, efficient machine systems (or retrofit for old machines) that can do job shop work with lights out capability, seem to be a huge growth area.
I will try to start some boring cashflow positive busineses such as opening a restaurant, bar etc. Once the business is stable , i can delegate to a team and have an income stream. Then, I will probably try to create a software that solve some pain points and try to sell it. I will keep the costs low and be ready to experiment and fail many times. Because i have an income stream, the failures won't crush me.
I would start ERP development and consulting business. First I would try to get some work from larger consultancies while also looking for some direct customers for myself.