Thank you for the detailed message. Definitely leaves me with more reading.

I now understand why they use primes. Can you please confirm the process of getting 2 primes and multiplying them then converting to 256 bits? My initial research people were saying you can generate a private key manually by flipping 256 coin tosses. That process has nothing to do with primes and it produces a valid private key so this is why I am confused.

You must be referring to RSA private keys.