Should I create a new wallet or import an existing one?

Create a new one if this is your first wallet. You set a password, and the wallet generates a seed phrase — write it down before you go any further.

Import if you already have a wallet elsewhere. There are two ways, and they are not equivalent:

• From a seed phrase — 12, 15, 18, 21 or 24 words, separated by spaces. This restores the whole wallet, and you can add further accounts to it later, all covered by the same backup.
• From a private key — restores exactly one account. There is no seed phrase to derive more from, so the account-management options stay hidden.

If a phrase or key is rejected, the wallet says only “Please check again” — usually a mistyped or missing word, or a word in the wrong order.