I have absolutely zero background or knowledge on coding/programming/IT/software/computing etc, but I’ve recently taken an interest in it. How much time, effort and resources would I need to sink into it in order to become at least borderline competent?
One (very imperfect) way to evaluate this is to look at the length of “coding bootcamps”. https://www.schoolofcode.co.uk/ , for instance, is 16 weeks of instruction - around three months. You could get a lot out of looking up bootcamps, seeing what they cover in how much time, and then DIYing it.
(I wouldn’t actually do one, they can be pretty exploitative).
Worth asking what you want to be proficient in, though. Not all programming is the same; you could become proficient in basic web junk to commercial standards pretty quickly compared to, say, putting together desktop applications to a decent standard.