Doing something completely new with my life, need some advice

I worked for 9 years as a petroleum engineer, doing mostly upstream ops for a company, and it paid well, but it bored me badly, and I never enjoyed going to work. I quit about a year ago, wanting to become an entrepreneur of some sort, but I have been very stuck, and have no idea what to start, or even what to do.

I have considered learning programming enough to where I can build mockups and prototypes, and maybe create something to serve people in some form or fashion.

Maybe I shouldn't have left my job without another rope to grasp, but since I want to completely phase out of that industry, I didn't feel like I had a choice.

I am currently financially sufficient, I have over 1.5 million invested, and I net over 140k on average per year, and pay myself 36k per year for living expenses, while the rest in re-invested.

I'm 32 with no kids or debt or anything, and I do have an engineering degree, but I wasn't a very stellar engineer, I mostly just gamed the system and got by, graduated with a 3.2 gpa which says a lot about my lack of commitment and focus.

So I'm pretty trapped now, but since I do have time without worrying about financial or personal obligations, I think I should be able to make something happen.

I feel like if I could intern or work with entrepreneurs, I would surely figure it out and go from there, I'm just not sure how to actually do such a thing, since most of them are very focused and only looking for full time employees.

Sorry this is such a broad question, but I could really use some advice on where to go from here.

I have been reading quite a bit, but all the books seem very general, and not particularly useful in actually getting me started on something.