I know almost nothing about this “academy,” but over the last several years, a glut of private online schools for graphic design have appeared. They’re leading to a glut of inadequately trained designers who will likely never find steady, well-paying work in the field since they’ll be competing with better-trained, in-person university graduates.
In the US (where I live), a BTEC diploma is more or less the equivalent of a 2-year Associate Degree in a technical field of some kind. Here, this isn’t usually enough to easily land a graphic designer job in a field that is increasingly requiring Bachelor’s degrees. However, it is often enough to land a job in a related field, such as print production or sales when combined with experience, interest, and aptitude.
Much depends on your interests, though. If you plan on becoming a professional graphic designer or art director, I’d recommend a university education. If your interests run more toward the technical aspects of production (or something similar), this online school might be OK.
First, I’ll make a disclaimer: I’m skeptical of online programs. Some fields might lend themselves to online learning, while others don’t.
There are two separate and important aspects of graphic design. The first is learning to see, think, and solve visual communication problems like a designer. The second is learning to use the tools (nowadays, mostly software), along with the technical aspects of the job, whether it is coding, preparing artwork for print, or something similar.
I can imagine learning the technical (software) aspect of graphic design online. However, I can’t easily imagine learning to see, think, and solve problems like a graphic designer online. To me, it’s the equivalent of trying to learn to play the piano or learning ballet online. Learning the basics from self-directed study or through online courses might be doable, but advanced and deep learning takes place when directly interacting with instructors and fellow students in person. There is no equivalent online substitute for that in my opinion.
You mentioned teaching yourself online. The trouble with this is you don’t know what you need to learn, so you’ll end up focusing on what interests you or what you naively think is important. You’ll inevitably end up with huge gaps in your knowledge. An Adobe Professional Certificate is mostly a useless credential that says you’ve learned the ins and outs of using specific Adobe software programs. Working through one of these courses, is probably a good way to gain experience in using Illustrator, but learning how to use software is not the same as learning design.