Kim has posted several articles pointing out some potential security issues with the Zoom program:
Warning: This program is sharing your Windows credentials every time you click
However, that said they due use encryption and take other measures to protect your privacy. There are details about the security they implement here:
https://zoom.us/security
If you have a G-Suite account (a business Google account through work or school) then Google Meet is a great option. We have been using this while working remotely to have our team meetings. Here is information on their security:
https://cloud.google.com/blog/products/g-suite/how-google-meet-keeps-video-conferences-secure
If you do not have a G-Suite account, you can sign up for one for as little as $6 a month: https://gsuite.google.com/pricing.html
The other members can join the meeting with a regular Google account, but the person who creates the meeting must have G-SUite.
Skype is another option that is free:
https://support.skype.com/en/faq/FA31/Does-Skype-use-encryption?