Why don't I execute my ideas?

I consider myself reasonably creative, I test high in openness, in high-school I started my own web development company, followed by an IT reselling business, I'm now 23 and I'm at a loss, I no longer start things or execute on my ideas, I have some things that I could start doing right now that will provide some fulfillment and possibly reward me financially, instead I procrastinate, and put them off, and off, and off. I have ideas, I start a folder and write the general idea out in a textile but then it just sits there.

I spend most of my time researching things I'm interested about, reading blogs or online articles on various topics, and I never do the work that could actually improve my life, let me give you some examples:

1. After getting diagnosed I found out I had an interest in maths, I want to re-learn as much as I can from scratch and go from there, instead of going home and setting out some time to learn it, I go home and procrastinate.

I have my suspicinons on why this occurs, one being that I think I am scared, scared of failure, I was diagnosed with ADHD recently and after long weeks of research and talks with my psych I've realized just how much of a negative impact it had on my life, it gave me some opportunities because I think outside the box and had personal interests that were valuable in the Job Market, but it also took those opportunities away from me in a very cruel way. I'm now on meds and I'm getting better, but I think those early childhood setbacks that could've been avoided affected me quite a lot, I want to explore this more with my psych.

But this occurs to people without ADHD to, the low unconsciousness idealist is a common trope, so I'm wondering, if you had to guess or make an informed decision, what would the main causes of this be? I'm leaning towards fear, but I'd like to hear your thoughts.

I realize this is a talk to have with a psychologist btw.