http://walletor4zewusprp5vknxboa7rigde3c25p7rcsxqrxaep3d7oag5id.onion/faqs.html
You can check the links below to know more about importing private keys: https://www.exodus.com/support/en/articles/8598622-how-do-i-import-a-private-key https://bitcointalk.org/index.php?topic=5096376.0 https://electrum.readthedocs.io/en/latest/faq.html#can-i-import-private-keys-from-other-bitcoin-clients The private key in question is a secret alphanumeric sequence that allows bitcoins attached to it to be spent.