Automatically email Instagram posts to subscribers (with invitation option) using Zapier or something like it

What I have:

Host: SiteGround
Website:
Wordpress website
OceanWP theme
Ocean Extra
Elementor
Elementor Pro
Essential Addons for Elementor
Contact Form 7
Contact Form CFDB7
Send
Site Mailer
WP Forms Lite
Instagram:
@FlowersOfPortland
@OldCarsOfPortland

What I’d like to build:
1. Form on website to subscribe to Flowers (already made with Contact Form 7)
1. Name
2. Email address
2. When visitor fills out form, add their name and contact info to database (should be automatic)
3. Regularly export WP database to a Google doc (once a day)
4. Use Zapier (or equivalent) to email to entire database every time I post to Instagram (@FlowersOfPortland). If using Zapier,
1. Modify Zapier’s standard email
1. Move invitation link below picture
2. Move unsubscribe link below picture
3. Configure From so that the email comes from me, not Zapier
4. Add About Me link that takes people to main page of website
5. If someone unsubscribes, discontinue emailing to them, but maintain the contact in a do-not-email list
6. Form on website to invite someone to subscribe to flower pics (already made with Contact Form 7)
1. Name of person they want to invite
2. Email of person they want to invite
3. Their name
4. Their email
7. If someone wants to offer someone else an invitation to receive flower pics,
1. Send email inviting them to subscribe (naming inviter)
2. Send email thanking inviter for inviting
3. Add inviter, invitee, to a different database than the one being used for sending emails

Seems like Zapier would be a good way to go with this, but I'd be open to using Constant Contact or another service if that makes more sense.