Hello, since I want to learn more about bitcoin and how you would ago about a wallet, I'm stuck with being able to spend coins to an address derived from an extended public key ( non hardened) since you don't have the private key to do so unlike hardened keys. Say I use the BIP84 implementation, thus the derivation path being m/84'/0'/0'/0/0 for the first receiving address how do I get hold of the private key of said public key to allow me to sign transactions?
Thank you in advance!