Two minutes. Everything can be changed afterwards from the admin area.
Create the database and its user in cPanel first, and give the user all privileges.
Must be HTTPS, and short: the payment confirmation URL built from it has to stay under 95 characters.
Where the red expiry notice sends your customers.
Leave empty to accept only the keys created here. Fill it in and keys issued by your WcPay activation system on WordPress activate here too.
Leave the SMTP host empty to use PHP's mail() instead. On shared hosting that usually lands in spam, so a mailbox on your own domain is strongly preferred.
465 = SSL
At least 10 characters.
Install