In my case it has been perseverance and dedication. I'm 120kg and 6ft4. I feel ok, but I am at least 15 kg over weight. I have two kids, and I realised I was getting less able to do things they wanted to do with me. The timeframe where they will actually want to do things with me is getting shorter too, so I've been running to improve my health and general fitness. It's painful, difficult, and I end up pretty sore, but I'm getting a little bit better each time, and I'm sticking with it this time. So I guess to answer your question, you get started by deciding it's time and the various reasons you have are important enough to keep trying. I let my health go during the pandemic and I really needed to do something about it for my family. If you're able, I would start with brisk walks, that gradually turn into periods of jogging on the walks, which gradually get longer.... Good luck