Why not start with what YOU can do...like Right Now.
My friend as I started reading I was hoping it's not anything due to lack of general simple healthy lifestyle habits as in food and physical activity.

But then I saw 'prediabetic' and I'd to take a deep breath. The only consolation -- if that's even the right phrase -- is that you are among the majority of the population. But we all know Diabetes is terrible disease. What's even more surprising that T2D is also preventable. Wondering how old I am? 80. And honestly some of my motivation comes from the fear of this frightening disease. So before I sat to type, I'd just come back from a grocery shop. Before getting there there's a 15 min walk and some park, So I said I haven't walked, why not go back the length of the park and use enjoy extra walking. On reaching home I had 25 lbs of groceries. From bus stop to apartment walking up two floor to apartment, I said: hey, wanna see how many more floors you can do,,..for the heck of it? Went four more floors as legs seemed crumbling. Walked down to my floor. This is to give you My example of 'Right Now" what we often can do.
Thank goodness, no meds, tests, surgeries and few visits to GP in life. And no I'm not lucky; with humble resources it's possible to maintain healthy lifestyle. I might do some dips or push ups before dinner under 5 minutes.

But I suspect you might already KNOW that. So I'll admit while some fear of becoming dependent is a spur, the larger reason is to be able to pursue my Purpose in life,,,far easier in an healthy fit bodymind. So I need to be pretty satisfied with the purpose I pursue With the Pleasurable means. It's almost impossible to live a life on-diet and exercise forsaking simple pleasures of surprise, awe and curiosity, of friends and refreshing sleep of my 8 hrs. Or finding humor in news, as well as challenges and frustrations. Not-Bad life is Good-enough for me.
Let me know your progress.