You can bulk import sending accounts into Instantly from a CSV file and to learn how, please watch the video in this article or follow the steps from below:
Create a copy of the file so you can edit it and fill out the account details
Fill out the columns (If you have just one password, or app password for your account, use it for both the 'IMAP Password' and 'SMTP Password' fields)
Outlook/Microsoft365 or Outlook accounts purchased via Godaddy, can't be connected via Bulk import, since it's only possible to connect them with the Microsoft connector, using oAuth.
When using an app password (for Google, for example), simply use it instead of the regular password
Google accounts, on the other hand, can be connected via bulk import. Enable IMAP and create App Passwords for each email account, use the app password as IMAP and SMTP password in the CSV file. Find IMAP and SMTP hosts here.
Save it as CSV (if you are not sure how to create CSV, check this sheet)
Upload it to Instantly by going to Email Accounts - Add New - Any Provider -Bulk Import from CSV
Map the fields and click Upload All