I grew up behind the iron curtain and have been taught to be afraid and careful of everything. That engraved a deep risk aversion towards anything.
However the richer and more experienced I get I feel a lot of FOMO and envy especially for those that managed to pull something off.
I feel like trying a side project is very risky and I should rather invest into climbing the corporate ladder (although deep down I know that's a dead end especially in Europe).
So my advice is find safe ways to become familiar with the outcomes. Put yourself in situations where you will fail, or most likely will, but the stakes are low enough that it doesn't matter.
If you're worried about risking your time and energy on a side project, do a weekend version of it first. Find contests, hackathons, challenges that provide a scaled down, structured version of whatever you want to do and do those. Immerse yourself in the space (don't pretend to be an expert, just learn all you can), help people on related projects, and soon enough it won't feel risky anymore, you'll have a realistic intuition of the outcomes.
Also, beware of letting FOMO and envy motivate you. Those evaporate quickly.