what would be a good step forward for a person who's looking to work from home because of health issues?
Are you looking to be an independent consultant in your own business? Or work for a company, but from home?
It would probably be best if you can hire on with a consulting firm first. I don't know how it is in Croatia, but here in the US, working for yourself can be a real challenge in terms of making enough money. When you work for a company, benefits often count more than actual pay. This is particularly true when it comes to health insurance, the premiums for which can be prohibitive when working for yourself. If you have, or plan to have a family, company benefits (insurance, paid vacation, sick pay, retirement plans, etc.) can really be important.
Sadly, I am not sure the WU or MR academies are will help much in terms of resume/CV material because they are not "accredited". You could certainly mention them with your experience.
When I was making my way through the corporate IT world after I got out of the Air Force in 1995, the corporate world was screaming for IT people, CompSci, programmers and anyone with experience. Even as an electronics technician with a degree in Electronics Management, my experience working with computer hardware and networks got me a great job at a big software development company even though I knew nothing about programming.
The problem is, universities really ramped up their IT programs and started pumping out IT grads right and left. So when I retired (again) 10 years later from that company, new hires with similar qualifications earned considerably less than I did when I first hired on.
Even with people, it is a supply and demand thing.
IT is still, and likely will always be a growing field, but there typically is a lot of competition for any open slots. So you really need to stand out. Security is the way go. So I think your interests there is spot on. Forensics is a totally different area, however - even though related. Remember, IT is many industries within many industries. The demand for experts in forensics is much less. Now if you are interested in Law Enforcement with an emphasis in forensics, that may open some lucrative doors. But not sure working at home would work however, as chain of custody issues may get in the way.
As for specifics for what you need to do today, I recommend you talk to your professors, and your school's IT people and ask them where the jobs are. Check the "help wanted" sources in your area and see what companies are looking for.