ELI5: How did ancient humans see tall growing grass (wheat), think to harvest it, mill it, mix it with water then put the mixture into fire to make ‘bread’?

I am trying to comprehend how something that required methodical steps and ‘good luck’ came to be a staple of civilisations for thousands of years. Thank you. (Sorry if this question isn’t correct for ELI5, I searched and couldn’t find it asked. Hope it’s in-bounds.)

Edit: thank you so much for all these thoughtful answers! It’s opened up my mind. It’s little wonder we use the term “since sliced bread” to describe modern advancements. Maybe?