Reinventing the wheel it’s ridiculous hard because of lack of information, sending a simple transaction.

A few days ago, i tried to create a script to automate sending gas to my wallets, i found the web3 library but decide to reinvent the wheel a little to understand how exactly signing works, almost 1 week after and i have barely started *rant alert* BECAUSE THERE IS NO FKING INFO *rant ended*, to be exactly there is no info about how exactly ECDSA returns the v, r, s values in Ethereum, how to send this info using eth_sendRawTransaction or other rpc method, how to sign the transaction, if i use eth_sendRawTransaction how eth knows the info about the transaction if the only sended is a hash, etc… i keep finding questions and no answers, where can i find this info or at least a step by step explanation of how to send a simple transaction?