Firstly, I think there are a couple of things that you should be honest with yourself. Do you truly love programming and what it can do to help you achieve your goals in live? Or are you just doing it because you see the fat paychecks that developers get? A good programmer has to be driven by passion as there is so much going on in the tech world, that there's only so much you can take before you burn out. Genuine passion helps alleviate that but even then, it is not uncommon for developers to change projects, albeit in the same industry.

Are you currently employed? If possible, come up with scripts/software to help you at work. Once you finish them, don't just abandon them. Always look for ways on how you can refactor your code to improve it as that is one of the best way to apply new knowledge gained over time.

Start a github repo as well and upload any projects you start and use that repo as part of your resume. If you truly believe you have what it takes, all you need is just constant practice and a github repo helps with accountability and experience on your resume.

If these people can do it, then 40 doesn't mean jack shit tbh.

I believe that if you show the right mentality, he's probably going to be fine giving you a chance. You'll be able to pick up all these things at a much faster rate from your colleagues.

We should remember it's close to impossible to completely remember everything in a language or framework by the word and that is why knowing how to refer to documentation is incredibly important. If your future employer understands that, you should be able to land yourself a job.

All the best to you in the near future.