Richard Dawkins has an entire chapter on this exact topic in his book “The Greatest Show on Earth”. I highly recommend reading it, even just that one chapter! It doesn’t feel like a text book, and his writing is very easy to follow in my opinion.
It’s chapter 8, “You did it yourself in 9 months”. To summarize, many people mistakenly think of genes as a “blueprint”, but he suggests it’s better to think of genes as instructions for origami paper folding. Genes don’t know the whole creature, they just know what to fold next, what to duplicate, what to bend, and so on, kind of like that. It’s been a while since I read it. 😅
But I do remember, humans are so complex, we may never fully understand the complete embryo-to-adult growth process, BUT the author points out that there IS a creature, a very small worm, that we are able to understand everything.
That may not seem like a big deal at first, but think about it. Scientists understand the complete growth process of a living creature, from a single cell, every gene, every cell, everything, up to when it’s fully formed. So cool.
I don’t know if this is it but, what you describe is called “imposter syndrome”, if that helps. 🙂