As for software engineering:
I have a BA in English and a PGCE (Secondary English) and I started learning to program at the end of maternity leave. I'm not applying for apprenticeships as my degree is non-STEM and I'm progressing through the application process nicely so far. I've been invited to one assessment day (but not happening until July) and I'm waiting to find out if I'll be invited for another and I'm at the first interview post coding tests on another. So a Level 4, 5 or 6 apprenticeship could be worth it. I'm focusing on 2 years.
If you have a STEM degree you could look at Graduate programs. Some will want a STEM degree, but you may find some open to non-STEM graduates as long as you can prove your programming knowledge via Github.
Another choice would be a coding bootcamp or Udacity. No formal qualification but sometimes cheaper than an MSc and a way into Software Engineering. I know plenty who've made the switch without a STEM degree, and some without a degree at all.
That said, learn and practice now. Build a portfolio. Complete coding challenges. Participate in hackathons. Google runs challenges which could lead to jobs. I'm sure there are other companies out there that do the same.
For the others, some of the above will apply. There are apprenticeships out there and online courses that could help. You could look at CompTIA, Google, Microsoft, RedHat and other IT certifications options if your looking to get into IT support and then developing further as a Sys Admin or Network Engineer. It really depends on what your area of interest is.