I've been employed in the field at the same company (over 40,000 employees across the major continents) for 13 years now doing software development and recently started on my Comp Sci degree (backwards I know, but I had been programming for fun for many years prior). I'm about halfway through and am learning things at least which is great! Fortunately I've been doing Java development for most of those 13 years so actually coding is easy for me at this point and I can focus on learning the science.
It sounds like you've not coded before. Why is that? Why do you want to get into comp sci? Be honest so we can make an honest assessment.
You'll likely want to be a self-learner. Comp sci is continuously evolving and not being able to adapt to that will hold you back. I have colleagues that are of the mindset, "I know what I know and that's what I know". You can get away with that but eventually your technology will get replaced with new technology. If you can't adjust you'll be stuck updating the old system until a new system is built and then politely shown the door. Work likely won't train you for what you need so you'll need to learn that on your own time. It likely won't be as difficult as pulling a full degree off of course, it'll just be applying old techniques to a new language or feature set. But you'll have to do some digging for sure.
Math is obviously important. So far I think discrete math and combinatorics has been the most helpful for me.
A lot of comp sci I think is knowing what is available and being able how to use the tools quickly along with being able to ensure your research is up to date. I certainly don't know everything about computers and never will, but I try to keep up to date with what's going on so in the future when a problem is presented to me, I can think "Hey there was that thing I read about briefly a bit back, I wonder if that would help here?"
There are some really good opportunities in comp sci and some really poor ones, I imagine just like any other field. You can potentially travel quite a bit if you go the contractor route. That's not for me but some really enjoy that. Most larger companies these days need comp sci people for something so you have potentially good opportunities to try for a company that interests you.
If you have specific questions, feel free to ask.