Really nice motivational blog
I started running in Jan 2023 at 33yo. Finished a half marathon later that year, and finished my first marathon (3h46min) two weeks ago, after almost two years training. In fact, you pointed it perfectly: first you start (done rather perfect), then you improve, by sticking to the process. I now run almost every day, and while the goal for the first year would be 1,000km in the entire year, I ran more than 2,000km this year already. Good luck in your half marathon, if you already figured it out mentally, the training process will be by far the easiest part. Your mindset is ready, now the mind will shape the body.
as a life-long runner: sounds like you are being very smart about your training plans. may i ask which book you will be using?