- What is the BTC address I could use for creating a transaction?
Any valid testnet address. You can get one from Bitcoin Core using the
- How do I "unlock" it to be able to send a transaction?
walletpassphrase <passphrase> <timeout> command where
<passphrase> is your passphrase and
<timeout> is the amount of time you want the wallet to be unlocked for. The wallet will automatically lock itself after the number of seconds specified in
- How do I add some BTC to it to be able to send it and/or pay for the transaction?
To get regtest coins, you need to mine them yourself. Bitcoin Core can quickly and easily mine a bunch of blocks, just use the
generatetoaddress command. Note that newly mined Bitcoin only become spendable after the coinbase transaction that produces them has 100 confirmations. So if you mine 101 blocks, you will be able to spend the 50 Bitcoin from the first block mined.
For help with the RPCs, there is a
help command. You can use that to get a list of available commands. Their names are pretty self explanatory. You can then do
help <command> where
<command> is some command you need help with. This will give you a more detailed description of the RPC, the parameters it takes, and what the result it returns will look like.