How did single celled organisms evolve into multicellular organisms?

Question

I feel like this part of evolution is kind of skipped over by historians. The more I think about it the more it hurts my brain

In: Biology

Answer 1

Because some organisms dna got mutated and it allowed it to be multi? Very small chance for it to be a mutation that actually works, but that’s how evolution works.

99,999 out of 100,000 mutations are completely useless and will probably downgrade the organism.

That 1 other mutation though…

Thus over millions of years, and millions of mutations among millions of organisms, we get humans.