Make sure you have some properly recorded music and (at least) still life images that can be used to promote yourselves.
Get an online sales account with somewhere like Spotify whereby people can go to buy your music and upload your songs, individually or probably better as a 4 track EP or album.
Get yourselves a PayPal account for the band.
Identify a number of other bands whose audience are likely to be interested in your music and find (and join if necessary) their Facebook/Instagram and Twitter accounts.
Launch the promotion of your songs and of the “event” with a free song to get people interested via your own social media and by posting into pages of similar bands.
You could also consider a small Facebook Ads programme, targeting the type of music and age bracket relatively near where you live (this is for the long term for promoting live gigs when you are able).
When you send details of the free song tell them about the date and time of the event and ask people to send in questions that will be answered at the event.
Remind people about the event on a periodic basis before and mention some of the questions that will be answered. Promote the event as “an event” via social media referencing the local time (some viewers will be worldwide).
The event itself will be a filmed concert performance, so if should be treated as such (movement and stage dress as if at a real gig) but in between each song the questions should be answered, ideally by various members of the band.
During the event, promote where the rest of the music can be found and also how donations can be sent in to the band.
