As you are learning, I suggest you test a complete workflow. After setting up the cold wallet, from a wallet where you have some sats send it a small amount (~10K), then wipe the cold wallet, restore it and send the sum back to the original hot wallet. If all works your setup is fully operative and you can start to send what you want to the cold wallet. Mempool is currently quite empty, it's a good moment to do this sort of test.