"In my experience you only get to know your characters through writing."
If I can offer another perspective @AlbertBridge...
I completely understand where you're coming from with this, and need to know my characters pretty well before I can write convincing action and dialogue. Otherwise, although I can write, what I produce very rarely takes me in the direction I want to go. Doing that as an exercise can be fun or useful, or can help you get past a block, but if you have a project or plan you want to get on with realising then time spent working on characterisation away from the writing process can pay huge dividends imo.
My advice is to spend a lot of time with your characters in your head. This can be hard to allow yourself time for because it doesn't feel like "writing" so much as daydreaming, but it's equally vital work, especially in the early stages imo. If you have any kind of sense of your plot, think about how your characters might act/react in a scene from that plot. (If not, just work randomly with a workplace or domestic scenario that might be relevant.) See it in your head like it's something you're watching on TV; hear the lines they say; observe the body language; think about whether - as a viewer - you believe in them, and if not why not; why are they saying and doing the things they are; what might it mean or lead to, etc. If it doesn't ring true, rework it in your head until it does.
When I get stuck on characters, I spend an hour or so before I sleep at night going through that kind of process, and then try to write what I saw the next day. If you do that every evening, you can get a lot written each day and after a while your project will start to take on a life of its own. Those scenes can always be abandoned or reworked later if the plot or characters seem to require it, but they can be a good way of getting to know your characters and asking yourself questions about their motivations. It can also stave off the sense of feeling blocked that quickly sets in if you want to be writing but don't seem to be able to.
I am also falling behind, although I'm not sure that's a helpful way to look at it. I have things going on in my work and personal life and that is just the way it is. But I agree with @Drybird2020 that the important thing is just to make some progress each day - either in writing or in your head - and to stick with it for this month so as to make a habit that will last far beyond. Ignore the word counts people are posting if that helps because for most of us here it's not a competition. (I haven't even officially signed up to NaNoWriMo, so I couldn't win even if I wanted to.)
If you commit to sticking with it, I will too. Let's see what we might manage in a month. 