There are a ton of ways to get into coding, but for career-changers, the two most common ways are by attending a coding bootcamp, or by self-learning. I'd definitely recommend starting with some free or low-cost online courses first to see if you enjoy coding, at which point you can decide if you want to continue with self-learning or consider something like a bootcamp.
If you become a software engineer, you will have to do some self-learning at some point - it's pretty much a job requirement.
I attended a bootcamp, and it was definitely the right call for me. In my experience, there are two main benefits to attending a bootcamp over self-learning: