This question is a bit board and probably opinion based. But here are some tips.
Do not think on "I want to be a graphic designer" Think about "I want to do 2D Infographics" or I want to do "3D motion graphics that look like this".
- Find time.
I doubt you are a slave. Use extra time. Sacrifice that Netflix show you are watching or 20 mins of sleep.
- You are living in the youtube era.
That is a blessing and a curse. Similar to point 1. If you find an objective. Doing a 2D infographic, DO IT!. Do not just look for a tutorial.
- Find some specific courses.
Similar to point 1. A course about infographics. Two courses about color, another course about flat design.
If they have some certification that would be good in case you need some documentation, but use them to get a nice portafolio.
- About studying a degree
That is a possibility if you really like it. But that is a personal choice. But probably... the sooner the better.
I do not know if there are affordable degrees on the place you live in. You need to balance that. But in this profession, talent is more valuable than a degree. If you find yourself in a job where you are appreciated by your talent, there is a chance that you can negotiate time to get a degree.
But this is totally opinion based.
Probably one difference between studying a degree vs studying by yourself is that a degree starts to form the general to particular. You study general design methodology, visual language, syntaxis, semiotics, etc, and then you specialize yourself in whatever you want.
Studying by yourself cannot be the same process, because you need more focused motivation. In a degree, one motivation is finishing the degree. When learning by yourself you need to find rewards by doing cool stuff.
And by studying a degree later you will find a methodology and fundamentals to your "style" and point of view.
In a real-life portfolio, staying focused is also a good idea. It is better to promote yourself as a specialist in something. Vector Illustration, motion graphics artist, editorial designer, rather than scattered products.
A wide variety of products is better if you are a design firm.
Think of a Photography studio.
"Product photography studio" vs "We shoot whatever we have in front of us"
Of course, the second one could work if it is a studio that creates visual effects and has a production crew, 3D department, etc. But as a person, the first one will work better.
One kid that is 18 years old needs more time to define what he wants to do, so the general-to-particular is excellent.
As you are 30, you probably know what do you want and like more.