4–6 digits. There's no email here, so if you forget it an admin resets it for you.
Both are on your DUPR profile. Nothing connects to DUPR — this is a one-time starting point, replaced by your real results here as you play. Leave reliability blank if you'd rather not say; your rating then carries a ? until you've played a session or two here. A typed reliability fades over the following months unless you play here.