Hey there @Sandy65332 -- great questions!

1. Yes. Any cancellation also stops reminders.
2. Yes, same as above!
3. This one is a little more complex, so let me break it down for you.
   1. All booking notifications that are email confirmations will be sent from notifications@calendly.com.
      1. Calendly sends the invitee an email notification from notifications@calendly.com and has a reply-to address that's associated with your Calendly login email. You can modify this on Account Settings page.
      2. You can select "no reply" if you don't want to receive replies or expose your personal email address. Instead, the email will come from no-reply@calendly.com.
   2. All booking notifications that are calendar invitations will be sent from your add-to calendar on your Calendar Sync page.
      1. your connected calendar sends the invitee a notification of the booked meeting which has a reply-to address that's associated with your Add to calendar email.
      2. There is no way to hide this email address as your calendar sends it directly. 
4. With Workflows specifically, you can integrate a Gmail or Outlook email address of your choice to send follow-up and reminder emails etc. This means you can create an email address specifically for this purpose, if you’d like.
   1. Head to your integrations & apps tab
   2. Click “email messaging” 
   3. Choose either “Gmail for Workflows” or “Outlook for Workflows” 
   4. Follow the prompts to connect

I hope this helps!