If you are talking about public key then the prefixes start with "1" and "3" for legacy wallet then bc1 for segwit there is also segwit that start with "3".
If you are looking for more prefixes related to bitcoin you can check this
https://en.bitcoin.it/wiki/List_of_address_prefixes
The post below is right but if you are looking for public key prefixes I think a public key that start with xPub is what you looking for or a public key in a hex that start with 0?
Can you try to use this tool
https://iancoleman.io/bip39/ and generate a sample mnemonic and it will show all address and keys as your reference because we don't have a list of prefixes for public key.