Yes. Currently, Bali (Indonesia) requires all tourists to be double-vaccinated. You will need to show proof of this upon arrival - we recommend printing off your certificate to take with you.
Yes, but you can purchase a visa on arrival at the airport for around $50 - card or cash is fine.
Yes, it is under the 'Registry' tab - all online. However, your presence is present enough :)
The local currency is Indonesian Rupiah. There are money changers everywhere in Bali. We recommend using your bank card to just withdraw cash from the ATM once there - you'll get the best exchange rate this way. Just make sure to notify your bank that your going to Indonesia beforehand.